Moved Object Registration/Creation functionality into new ObjectRegistry class.  Hopefully this fixes the issue with the object map not being initialized yet since it is a static member of the class and should theoretically be initialized before code in functions of that class can be executed.  Seems to work for me, but I'll wait until Tazpn tests it to declare it fixed.

- There are no longer any defines, things like inheritance class name, NIF attribute variables, and default constructor code are all visible without looking at another file.
- All non-custom parts of the Object files are now totally identical and in the same order, so it will be easier to compare them.
- NiObjects are now completely self-contained.  To remove them from Niflib, you have only to exclude their CPP file from the build.  To add new ones, you only have to include their new CPP file.
- Making a change to a NiObject implementation file only causes that one file to be re-compiled, which is generally much quicker than before since the large obj_define and obj_impl files do not have to be parsed or compiled.
- There are no longer any "Internal" versions of the Read, Write, asString, FixLinks, or GetRefs functions.  Now there is just one function for each of these with pre and post custom code areas (except for GetRefs which I didn't think needed it.)
- Updates to the hierarchy in the XML should now be almost completely automatic.  All that should be necessary to make an update is to add any new NiObject CPP files to the build.
- Changes to the generated parts of the NiObject files can now be made at any time, and immediately applied to all NiObjects without editing each existing one.

Updated Niflib to the latest XML which adds support for bhkMeshShape, NiMultiTextureProperty, NiRawImageData, and NiSequence.

Objects now have a Create methods and register themselves in the global object map with pre-main initialization, making obj_factories.cpp obsolete.

Re-exposed TYPE constants and marked them NIFLIB_API, making the TypeConst function obsolete.  You now must use NiObject::TYPE instead of NiObject::TypeConst() again.

More documentation improvements.  Added documentation to NiDynamicEffect-derived objects, removed some obsolete examples, and replaced remaining references to "block" with "object" wherever possible.

Laying the groundwork for Niflib to be able to work on systems with different endian types.  All Read/Write functions now take NifInfo structures which are based by const reference.  These are also passed into the NifStream functions so they will have access to the requested endian type of the NIF as well.  Also added endian detection and swapping functions.

Moved TypeConst function implementation out of header file. Hopefully should fix GCC visibility issue.
Fixed GetIDString virtual function missmatch that was causing the name not to show up when the function was called from a NiObjectRef.
Added Python-specific operator functions to Ref to prevent the wrapper from crashing on Null Refs.

To allow for DLL mode, the IDENTITY constants in the Matrix classes were made private and are now accessible through the Identity() function of each matrix class.  This may affect the 3ds Max plug-in as well.

Fixed Niflib DLL compile.  All public functions should now be marked with either NIFLIB_API or NIFLIB_HIDDEN.  May have missed a few here or there but they should be noticed eventually.

ComplexShape::Split now cuts out weights below 0.1 and normalizes the result.
Fixed a bug which could cause NiSkinInstance to try to call a function on a NiNode that was in the midst of destruction.
Removed some cout statements.

Fixed the relative include paths and tried to update solution, but havn't got the precompiled header working right.

Renamed CreateBlock to CreateObject and made it clear that it is not necessary for the user to call this function unless s/he is working through Python.
Removed BlocksInMemory function.  Call NiObject::NumObjectsInMemory instead.
Removed CreateBlock template since new keyword can be used.
Implemented GetScale and SetScale functions of bhkNiTriStripsShape to fix linker errors when compiling Python wrapper.

Finished Skin API except for NiSkinPartition.  Part of this was making NiSkinData read-only with a new interface.
Fixed a bug in the SubtractRef function.

Commented out functions written by Amorilia that I need to figure out how to fix.

Major update to python generation scripts and others.  Currently just namepace and mutable size members with appropriate generated code.

Noticed that I had forgot to include NiObject.cpp in my last commit... unfortunately I've already started splitting off classes into their own files so that's included in this commit as well.
I also noticed that I never implemented the member functions of Ref!  I still haven't, but I was just surprised it's been compiling without complaint.