Added checking to for Periods were time diff is 0. Fixes test/lib/time-lord/period_test.rb
Added checking to for Periods were time diff is 0. Fixes krainboltgreene/time-lord/issues/13
Merge branch 'master' of github.com:bhaberer/time-lord
Merge pull request #15 from bhaberer/master

Fix for Time.now.ago.to_words => 0 years ago