Support Rails 4 (drop to support Rails 3.2.16 or older)

I can check it works well with simple Rails test only.
I use it with rails 4.1.4 so if I find bugs, I'll fix them ASAP...
doc: add 1.0.2 entry
doc: Use github.io as web site for test-unit-activesupport
doc: update supported version
doc: add my name as author
doc: add missing settings for locale to Packnga configurations
doc: update po

Sorry, I'll translate them later...
doc: translate