a couple of minor? adjustments

I made a few changes in order to get this to build and work for my project on OSX with Clang

a) I had to tweak the CMake files to make things work with Xcode.  I does build an Xcode project but I'm not sure that it's all correct.  That is I don't think the Xcode tests work as expected.  This is outside our scope - I think it's an issue regarding the CMake Xcode implementation.  It does build the library however and that was enough for me.  I seem to recall that I had some issues regarding the selection of static vs shared library build.  It seems that the best setup is to build a static library which links to the shared library version of the standard libraries.  This seems to contradict normal recommended practice of using all static or all shared libraries.  Hopefully I made the right choice here - but I'll leave it to the experts.  I'm hoping you don't think I'm the expert.

b) I need the parser to parse just part of the file.  It turns out that it consumed one more character than necessary when used with an input stream iterator. I "fixed" it by doing an unmet after calling the parser.  Again, I'm not sure is this really correct - I'll leave that to you.

Robert Ramey