remove attr_protected in favor of strong_params
replace active card with default card
Remove duplicate 'interval' param in example code
Removed the duplicate entries in the example in README
Removed duplicate attribute added in Subscription model
Removed duplicated lines for updating the owner relationship
Fixed incorrectly gsubing plan model for coupon
Merge pull request #19 from laktek/master

Fixed some duplications in README and generator script
Merge pull request #18 from marckohlbrugge/patch-1

Remove duplicate 'interval' param in example code
Merge pull request #17 from gregmolnar/rails4

More Rails 4 support.
Adding additional fixes for Rails 4.
Bumping version.