clib2 Code

- Moved the signal semaphore allocation/initialization/deallocation
into a dedicated module. This also has the advantage that it's
harder to break code by accidentally forgetting to call
InitSemaphore() after having allocated the memory for it.

- Added the missing header files required to rebuild ftw_ftw.c and
ftw_nftw.c.

- Reworked the code that handles quoting for the wildcard expansion
routine. We no longer allocate memory and then modify it, but
call a function for each quoted parameter which does whatever is
necessary.

- The shell command parameter parser now considers the non-breaking
space character (ISO code 160) to be a blank space character, too.

- The lstat() code now reliably detects that it found a soft link.

- Fixed the compilation problems I had introduced by mistake.

- Added atoll(), ffs(), ftw(), nftw(), lstat() and uname() code
contributed by Peter Bengtsson. Thank you very much!

- Cleaned up the header files some more; the POSIX stdio thread locking functions
are now defined as empty macros unless __THREAD_SAFE is defined.

- Updated the README file to mention the PowerPC platform, the floating point
support and the thread-safety.

- The translation of Unix to Amiga path names now silently accepts
absolute Amiga path names passed to it and will use them without
changing them.

- Extended the thread-safety locking to the file descriptors.