Added third method of implementing interfaces; inside the interface definition itself.
Moved built-in evaluation methods away from __X__ approach to overloads.
Revert accidental inclusion of local header file.

Blame KDevelop :)
Improvements to Android build process.

LLVM is no longer built during CMake configuration stage.
Removed templates for error and error_throw functions which should reduce
binary size. Added linker option -Wl,--exclude-libs,ALL to prevent
psi-tvm-llvm exporting all LLVM related symbols.
Binary size reduction optimizations.

I think this is about as small as I can make the various binaries as-is.
Merging shared object will reduce the total size a bit further, but really
I need to write an alternate JIT backend to produce a much smaller footprint.

For some reason Win32 tests are failing (at least under Wine). I don't know
at the moment whether this is because I'm mis-generating the LLVM IR;
it'll be much easier to debug from real Windows.