Log Message:
Update scheme48 to 1.6.
Patch provided by Yorick Hardy in PR 36335.
And added test target (but fail if effective user == root direcoty owner).

Release notes for version 1.6

    * Additions:
          o An autogen.sh script for generating the various generated files from \ 
source was added.
          o Infrastructure for creating, running and composing test suites was \ 
added. As a result, "make check" now runs more tests than before.
          o It is now possible for adventurous users to run the linker in PLT Scheme.
    * Changes:
          o make image now assumes a Unicode-capable Scheme 48.
    * Bug fixes:
          o A bug where automatic port-flushing would churn trying to write to a \ 
blocking socket was fixed.
          o An infinite loop upon (/ 0.0 0.0) was fixed. (reported by Taylor \ 
Campbell)
          o A bug that made system unusable was fixed. (reported by Marco Benelli)
          o A bug with package mutation, which made running the PreScheme \ 
compiler on the VM break was fixed.
          o Bugs related to the conversion between OS strings and strings on \ 
command-line handling were fixed. (reported by Andreas Rottmann)
          o Compilation using gcc now uses the -munaligned-doubles flag where \ 
available, which is needed on SPARCs to make floating-point arithmetic work.
          o Compilation older versions Cygwin that don't have langinfo.h should \ 
be fixed.
          o Some problems with installing and running on Windows Vista were \ 
fixed. (thanks to Axel T. Schreiner)

Release notes for version 1.5

    * Additions:
          o Comprehensive Unicode support was added. See the manual for details.
          o An implementation of SRFI 19 was added. (thanks to Emilio Lopes)
          o Syntax-rules now supports vector patterns and templates.
          o The ,bound? command now produces more output. (thanks to Taylor Campbell)
    * Changes:
          o Many of the POSIX procedures that accepted or returned strings \ 
previously now accept or return OS strings. See the manual for details.
          o The ,build command now accepts a procedure that will be called with \ 
a list of OS strings rather than regular strings.
          o The ascii->char and char->ascii procedures from the ascii \ 
structure covers only ASCII (codes 0-127) now. (Previously, the range included \ 
128-255 as well.)
    * Bug fixes:
          o A bug with package mutation was fixed. (reported by Taylor Campbell)

Release notes for version 1.4

    * Additions:
          o Regexp? is now exported from the rexexps structure.
          o SRFIs 4, 39, 40, 43, 43, 60, 61, 63, 66, 67, 71, 78 (mostly thanks \ 
to David Van Horn)
          o In the command processor, switches were generalized to settings, \ 
specifically to customize various printing parameters. See the manual for \ 
details.
          o A generic byte-code parser was added to the system; the disassembler \ 
uses it.
          o A reinitializers for register actions to be performed after resuming \ 
an image was added.
          o A variable-arguments-lists structure implementing a macro for \ 
dealing with optional default parameters was added.
          o A get-interrupt-handler procedure was added.
          o An --enable-universal-binary option was added to configure to \ 
facilitate building universal binaries on Mac OS X. (thanks to Eric Knauel)
          o The C code now has access to enum sets.
    * Changes:
          o File-options (in the POSIX libary) are now enum sets; this allows \ 
using enum-set operations on them.
          o Various changes were made to the VM to enable native-code compilation.
          o Socket addresses are always reusable.
          o 1+ and 1- are no longer valid identifiers.
          o The ordering of in/out thunks of dynamic-wind was changed to be \ 
consistent with itself and with the upcoming R6RS.
          o The Windows build is now done using Visual Studio 2005.
    * Bug fixes:
          o Macro-defining macros now work in PreScheme.
          o Opening a file for both read and write via the POSIX libraries \ 
wouldn't work correctly. (Reported by Andreas Rottmann.)
          o PreScheme's copy-memory! now works for overlapping regions.
          o Various C compilation problems were fixed.
          o cmuscheme48.el should now work under GNU Emacs as well as XEmacs.
          o Numerous problems with floating-point arithmetic were fixed.
          o A race condition with queues was fixed. (thanks to David Frese)
          o Part of script messages were printed on stdout rather than stderr; \ 
fixed. (thanks to Andreas Rottmann)
          o A shadowing bug in the debugging package was fixed. (thanks to \ 
Taylor Campbell)
          o A bug in the CML sync-group primitive was fixed. (thanks to Heath Putnam)
          o Various errors in SRFI 13 were fixed.
          o A bug in the auto-integrator was fixed. (thanks to Taylor Campbell)
          o A bug in load-dynamic-externals was fixed. (thanks to Taylor Campbell)
          o Several bugs in vector-merge were fixed. (reported by Matthias Radestock)
          o The CML wrap was made correctly tail-recursive. (reported by Heath \ 
Putnam)
          o A bug in the PreScheme C backend, that would sometimes incorrectly \ 
delete tail calls without a return value, was fixed. (reported by Eric Merritt)
          o Several bugs in interface walking were fixed. (reported by Taylor \ 
Campbell)
          o A bug in the PreScheme compiler affecting the removal of unused \ 
procedures was fixed. (thanks to Eric Knauel)
          o Some precedence bugs in the C stubgs for the regexp code were fixed. \ 
(thanks to Matthew Dempsky)
          o A bug in the regexps package for regexps without submatches was fixed.
          o (set-current-proposal! (current-proposal)) no longer raises an \ 
exception. (thanks to Taylor Campbell)
          o A bug in package caching was fixed. (thanks to Taylor Campbell)
          o A bug in the generation of environment maps was fixed. (thanks to \ 
Taylor Campbell)
          o The Windows installer package should now work even on systems that \ 
have delayed variable expansion on by default. (thanks to Emilio Lopes)
          o Exception handlers that return from raise are now handled correctly. \ 
(reported by Norbert Freudemann)