Making the gemspec more valid-er

to silence bundle install explosions.
Merge pull request #13 from travis-ci/db-gemspec-validity

Making the gemspec more valid-er
Test jruby-head (and allow failures)
Merge branch 'master' of github.com:travis-ci/travis-support
Do not run JRuby 9000 on Java 6

JRuby 9000 requires Java 7
Use 'rspec-its' 1.0.1

This is the last version to run on RSpec 2.x
Merge branch 'master' into sf-amqp-use-prefix-option

Conflicts:
	Gemfile