Implement 'scons cppcheck=1' functionality ... plus a few other minor updates

Generates the file 'cppcheck_report.txt' in the top level directory.

Add *.so.* to .gitignore so that the Hall C shared library with version number is excluded.

Removed -rdynamic compiler option from MacOSX configuration - SCons will add this automatically on versions of MacOSX (<=10.8) that use g++ ... On Mavericks (10.9) which now uses the clang (LLVM) compiler by default, -rdynamic is not a valid compiler option.