Log Message:
Update to 2.0

New in 2.0:

* Use ucontext.h provided functions for thread creation and switching.
  In case those are not available use sigaltstack for thread creation
  and sigsetjmp/siglongjump for thread switching, and if sigaltstack
  doesn't exist fall back on the old process.S assembly code.
* Simplified pthread support a bit, now it builds and runs on cygwin.
* RPM .spec file fix to allow non-root users to build (Matthew Rich).
* Included AIX process.S assembly, since I don't know the right ifdefs,
  it isn't actually part of process.S yet.
* This library is binary compatible with previous releases. But some of
  the prototypes of callback functions got cleaned up a bit so that
  building against this version of LWP will give some trivially fixable
  compile warnings or errors.

New in 1.13:

* Stack switching code for AMD64 processors (Brett Lymn).