clib2 Code

- Updated the general documentation and started to document the implementation-specific
behaviour of the library functions.

- In libunix.a malloc(), calloc() and realloc() no longer treat a
request to allocate 0 bytes as an error, returning NULL. They all
return a 1 byte memory chunk initialized to 0 instead.

- Replaced the sqrt() call.

- Added <fenv.h> for C99, and the (yet unimplemented) functions
feclearexcept(), fegetenv(), fegetexceptflag(), fegetround(),
feholdexcept(), feraiseexcept(), fesetenv(), fesetexceptflag(),
fetestexcept(), fetestround() and feupdateenv().

- Replaced the old pow() implementation. However, powf() may need to
be changed to set a domain error.

- Added more boundary checks to the FD_#?() macros which now also catch
the case of negative socket IDs.

This commit was manufactured by cvs2svn to create tag 'V1_197'.

- Fixed the Amiga archive build script to delete the remains of the
CVS directory structure.

- Updated the Unix archive build script to clean up the
CVS subdirectories in the "include" directory.

- Added Steven Solie's new OS4 build makefile.

- Preparations for clib2 1.197 release.