Reformat contributors
Replace .rvmrc with .ruby-version

The .rvmrc file produces an ugly warning about compatibility and trusting.
Replaced the deprecated source :rubygems
RSpec 2.14 support
Make .ruby-version rbenv compatible
Only bump the development version of RSpec to 2.10
Add @ozeias to contributors
Changelog
Add snippets of ResqueMailer to README
Update README and CHANGELOG with @yuyak
Deleting the rpec gem dependency
Changing also the spec heper requires
Changing also the matcher requirments
Rebuild Gemfile
Update README and CHANGELOG with @andresbravog
v0.14.0
Add license to gemspec

Closes #75
v0.14.1
Revert rubygems 2.0.0 requirement.

Seems it's not necessary given the facilities used in the gem, and imposes a burden on users to update.

In our case, we currently can't run our CI on tddium.

Was introduced here: 9e2a9fccef2d1a9480efebf81343a44826d10469
Add @Empact to contributors