Merged NeLibCore.c into Nerd.c

Now we only need to add Nerd.c to get a basic Nerd VM.
Parser reads ratios now.
Added support for short numbers

Numbers that can fit into 56-bits are optimised so that NeNumberRefs are not allocated in the pool.  Upped version to 0.22
True is yes, false is no.

Changed the boolean keywords to fit more into an Objective-C and Prolog mindset (because I prefer the language), and it's quicker to type :)
Fixed number parsing bug and added division by zero error.
Added commit version number.
Added version-string native, and changed version

'version' now returns a triplet list containing major, minor and commit values.  'version-string' is the old 'version'.
Fixed garbage collection bug.

The stack was not being marked.
Some fixes with macros and table printing.
Removed NE_NIL_ATOM.  It is now 0.

We will now enforce that nil will always be 0 from now on.
Added some test code to fix method env bug.
Updating project to work with Xcode 5.
Fixed crash bug and removed Xcode 5 warnings.
Merge branch 'development' of /Volumes/DEVELOPMENT/Git/Nerd into development
Fixed bug with loss of symbols in methods.

We were recycling environments that were used by closures.  This is not the case now.