Added MANPATH to opt-python modulefile

Python man(1) pages are installed at /opt/python/share/man and
differ from the OS installed man pages installed at /usr/share/man.

Adding the MANPATH directive to the modulefile prepends and removes
the /opt/python/share/man when the module is loaded and unloaded.
Bumped opt-python-modules version.
Added opt-python-modules to manifest
Merge pull request #6 from tcooper/MODULES_MANPATH

Added MANPATH to opt-python modulefile