Move to .ruby-version
- Upgrade to ruby 2.0
Simplified gemspec and dependencies
Upgrade to activerecord 4
- Removes deprecation warnings
Merge branch 'feature/activerecord-4-upgrade' into develop

* feature/activerecord-4-upgrade:
  Upgrade to activerecord 4 - Removes deprecation warnings
  Simplified gemspec and dependencies
  Move to .ruby-version - Upgrade to ruby 2.0
Remove old changelog
Prepare v1.0.0 release
Merge branch 'release/v1.0.0'

* release/v1.0.0:
  Prepare v1.0.0 release
  Remove old changelog
  Upgrade to activerecord 4 - Removes deprecation warnings
  Simplified gemspec and dependencies
  Move to .ruby-version - Upgrade to ruby 2.0