Log Message:
Update to lmdbg-1.0.0
  libstacktrace:
     Remove signal handlers and other garbage.
     All we need is __builtin_frame_address and __builtin_return_address
     builtins and nothing else.

  Documentation files have been moved to subproject "doc".
  Run "mkcmake install-doc" for installing it (or change SUBPRJ_DFLT).

  Only backtrace(3) in libc is accepted as an external implementation
  of stacktrace(3). This may fix build failure on FreeBSD with
  installed libexeinfo.