pmdabcc: add pid check/filter helpers, relax process check
pmdabcc: add pid check/filter helpers, relax process check

Allow process matching to match cases like /usr/libexec/pcp/bin/pmcd.
Mark methods needlessly classmethods as staticmethods.
Fix indentation in a couple of spots, few pylint / coding style tweaks.

adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp