add brace around a Python print called in jam script since print become a function in py3k

svn path=/sandbox-branches/bhy/py3k/tools/build/; revision=53276
add 2to3 support for bpl-test

svn path=/sandbox-branches/bhy/py3k/tools/build/; revision=55359
some debugging code for python.jam and add a dummy enum.py as dependent of polymorphism2_auto_ptr for testing

svn path=/sandbox-branches/bhy/py3k/tools/build/; revision=55360
corrected python version checking for 2to3

svn path=/sandbox-branches/bhy/py3k/tools/build/; revision=55441