Allow dont_blame_nrpe to be defined in the pillar

The dont_blame_nrpe setting is one that users would typically want to tailor to
their needs and we therefore allow them to do so via pillars.

This should fix #6.
Remove spurious p1_file entry from example pillar

p1_file is not set via pillars, but defined in map.jinja and this entry should
not have made it into the example pillar.
Merge pull request #10 from babilen/issue/empty_p1_file_pillar

Remove spurious p1_file entry from example pillar
Merge pull request #9 from babilen/issue/#6

Allow dont_blame_nrpe to be defined in the pillar
Define configuration file paths explicitly

Configuration file paths were previously derived from concatenating typically
used file names with the platform specific nagios configuration directory. This
patch allows for this to be overridden.