fix gemspec with ruby 1.9
do not report ActiveSupport::TimeWithZone differences that aren't relevant

See http://blog.tddium.com/2011/08/07/rails-time-comparisons-devil-details-etc/
for more details on that issue
fix version handling, bump version to 0.1.2
Merge pull request #1 from aduffeck/master

some .gemspec and ruby 1.9 fixes