Fix minor compatibility issues

add support for avro

enable PyStringObject and remove some workarounds inside the numpy patch

@rudi-c #1027 numpy patch with a small fix

By checking for the error state before the chosen CF call, we
know that it's not the CF call that set the error state.

Allow widths represented by subclasses of int and throw an exception
instead of aborting if the wrong types are given.

Also some minor cleanup of the NumPy test script.

Some of the patches are no longer necessary, as issues have
been fixed.

Use our interned ints more often (especially for constants specified inside the source)

Before we did not use the interned ints for constants inside the source code
so every module had there on 0, 1 etc...

switch to CPython parser

compile: Don't check for ''break' outside loop' error when in AST only mode

fixes for py.test

_warnings is modifying it

Add a modified version of cpythons ast test

Correctly align pointers inside registerPotentialRootRange

this showed up while importing a C extension

enable CPython's _ast module