Transfered type casting

Further optimise int/float comparison

Repair and simplify unrolled PyLong comparison loop that used PyLong_BASE incorrectly (it's an exponential base, not a factor).

Fix incrementally increasing indentation level in utility functions due to repeated opening braces inside of C preprocessor conditionals.

Speed up 1-argument method calls, especially those to CyFunctions, by avoiding the creation of a bound method object.

Transfered keyword only arguments.

Transfer optional arguments

Fix utility function in MSVC which does not support C preprocessor tests inside of macro expansions ("likely()").

transfered checked type casts

Transfered overriding in extension types.

Transfered warning from the reference guide to the user guide.

Improved "Types" section.

Transfered cdef statement.

Transfered declaring data types.

Reducing the overhead here is actually helpful since many KeyErrors will never be instantiated.

Transfered the Cython file types in the userguide.

Speed up the recursion to children in Visitor.py by avoiding cpdef call overhead (most transforms are Python classes with class dicts that require an override check).