Parse::PMFile - parses .pm file as PAUSE does

The most of the code of this module is taken from the PAUSE code as of
April 2013 almost verbatim. Thus, the heart of this module should be
quite stable. However, I made it not to use pipe ("-|") as well as I
stripped database-related code. If you encounter any issue, that's most
probably because of my modification.

This module doesn't provide features to extract a distribution or parse
meta files intentionally.