Added FSHELL_[NO_]ARMCC_DIAG_SUPPRESS_SUPPORT.
The versions of RVCT that I'm using (2.2 build 616 and 2.2 build 686) don't appear to support --diag-supress.
More build fixes.
Changed the documentation builder to automatically prepend %EPOCROOT% (converted to a path relative form) to pre-processor include path options that start with 'epoc32'. Prevously $(EPOCROOT) was prepended in the makefile, which broke the documentation build because the pre-processor will only accecpt relative path include options.