o Moved personal dev environment from older gcc to newer clang. Many small changes...

 o Moved personal dev environment from older gcc to newer clang.  Many small changes were made to satisfy the new compiler:
   - Altered many printf format codes to use the correct type for the given integer type
   - Parenthesized some expressions to clarify previously ambiguous expectations of precedence
   - Created macro KM_MACOSX for use in OS-specific code selection
   - Removed last uses of the old C-language abs(), now using Kumu::xabs()
   - Removed last uses of the old C-language atoi()
 o Added platform-independent call Kumu::GetExecutablePath() (test with win32)
 o Fixed a bug that was causing Array properties to be written without the (count, length) header (from PAL)
 o Fixed Win32 build (from Crowe)
 o Added imlementation of SMPTE ST 2092-1 pink noise generator
 o Added pinkwave CLI utility
 o Added font support to the IMF timed-text wrapper