remove .ruby-version
enable to use EVN['FLUENTD_URL']
fix required rails version
Merge pull request #7 from masarakki/remove-ruby-version

remove and ignore .ruby-version
Merge branch 'use-env-url' of https://github.com/masarakki/act-fluent-logger-rails into masarakki-use-env-url
Merge branch 'masarakki-use-env-url'
Merge pull request #9 from masarakki/for-old-rails

fix required rails version
0.1.4