added refcount information for PyObject_Call

Norwitz)

This code generated a C assertion:
        assert 1, ([s for s in x] +
                   [s for s in x])
        pass

assert was completely broken, it needed to use the proper block.
compiler_use_block() is now no longer used, so remove it.

Needs backport.

Fix _sys_version() so it works with the new buildno, not sure if it is correct.  test_platform passes

Fix some 64-bit issues due to mismatch format characters w/actual data types

Don't double check for NULLs and don't initialize if not necessary.
No functional changes.

Add C API function Py_GetBuildNumber(), add it to the interactive prompt
banner (i.e. Py_GetBuildInfo()), and add it as the sys.build_number
attribute.  The build number is a string instead of an int because it may
contain a trailing 'M' if there are local modifications.

We still need a change in the reference manual to reflect the
new try statement.

Modified since ast-arenas was implemented.

simplifies a lot of error handling code, and fixes many memory leaks.

(reported by Chris Olds).  Backported from the 1.0.6 development
branch.

just like string codecs.