Packaging cleanup: remove conditionals for < 2.6 support.

PEP 370 features and sys.dont_write_bytecode are always available
in 3.3; the distutils2 backport still has the conditionals.

I also renamed an internal misnamed method and fixed a few things
(“packaging2” name, stray print, unused import, fd leak).

Lib/packaging/compiler/bcppcompiler.py

@@ -352,5 +352,4 @@ class BCPPCompiler(CCompiler) :
             try:
                 self.spawn(pp_args)
             except PackagingExecError as msg:
-                print(msg)
                 raise CompileError(msg)