Fixes a problem where after dup the dup'd model and the original model share a translation instance, which means that if you mutate a translated field on the dup and save it, the original becomes a clone of the dup.
remove usage of Thread.current for fallbacks as this configuration is not thread-specific
remove all usages of Thread.local
Add frament caching note into README
Fix the way bundler works with rbx on CI

Per #380
Merge pull request #378 from scarfacedeb/cache_key_readme

Add frament caching note into README

[ci skip]
Merge pull request #374 from hube/fix-fallbacks

remove usage of Thread.current for fallbacks
Merge pull request #352 from hypomodern/fix-dup-translation

Fixes a problem with dup and instance variables
attempt to make it work with rails 4.2
make rails 4.2 compatibility changes conditional on rails version to stay backwards compatible
add rails version check via env variable to make tests work
fix rails 4.2 check and starting to work on tests
fixing some more issues
rails 4.2 needs table_name= above translates call for some reason
made dirty tracking work for rails 4.2
load dirty tracking patch only for rails 4.2 to keep backwards compatibility
removed rails < 4.2 support
fix merge conflicts