Most uses of PyCode_New found by http://www.google.com/codesearch?q=PyCode_New
are trying to build an empty code object, usually to put it in a dummy frame
object. This patch adds a PyCode_NewEmpty wrapper which lets the user specify
just the filename, function name, and first line number, instead of also
requiring lots of code internals.
Added PyFloat_GetMax(), PyFloat_GetMin() and PyFloat_GetInfo() to the float API.
Added a dictionary sys.float_info with information about the internal floating point type to the sys module.