Add pkg_prefix conf_attr to Koji module (rev 4)

Rebased against current master
Merge pull request #59 from ManageIQ/koji_pkg_prefix

Add pkg_prefix conf_attr to Koji module
Accept splat arg list in Polisher::VersionChecker#check
Move VersionChecker deps closer to use so as to relax hard deps
Optimizations & improvements to errata module (rev 1)
Merge pull request #68 from ManageIQ/errata-deps

Errata deps
v0.9.1 release
Fix incorrect syntax: s/Hasn/Hash
Enable tag inheritance in koji module
Fix a few small regressions (rev 1)

  - honor devel flag in gem dependency checker
  - flatten targets list in version checker
Merge pull request #73 from ManageIQ/regression_fixes

Fix a few small regressions
Merge pull request #71 from ManageIQ/koji-inheritance

Enable tag inheritance in koji module
Fix #37: raise errors on build failures (rev 2)

Also handle a few edge cases / add some syntactic sugar