Removed libxml dependency, performance improvements, variadic functions, mem fixes.

New for ~~0.0.16~~ (1.0.0?..):

Major changes:
* Support for variadic functions
* Support for block functions, passing in $(function(){}, [rtntype,['@', argtype1,argtype2,...]]);
* Added support for adding methods for class and id members (e.g., -sel and +sel).

Minor changes:
* Check was added to make sure null/undefined selectors cannot be passed in (previously it seg faulted rather than kicking out an error)
* Fixed crashing issue when using const "Classes" E.g., __NSStringConstant and internal types being passed through.
* Fixed issue 11 and 31 for casting bool's (e.g., returning true/false rather than 1/0), this fixed another issue I found later where an integer being passed as a BOOL wouldn't work due to the alignment.
* Fixed issue where segmentation faults happened if the size of struct was less than 16 bytes.
* Fixed garbage collection issue if a function result was passed into another obj-c function and added further memory/gc tests.

Performance Changes:
* Libxmljs is now replaced with a bridgesupport specific xml parser.
* The new parser is 41% faster and lower code footprint (maintenance).  
* The new parser uses 49.1% less memory (technically leaking memory fixes).
* Added a few new unit tests for performance/memory.
* Moved all wrapping operations into core to further reduce circular dependencies (almost there)

This passes all existing unit tests, minor changes to the API (Class.addMethod deprecated to support instance and class methods).