Added tests for Heroku Anvil strategy
Added json dependency to gemspec
Merge branch 'master' into heroku_tests
Automatically expand URL for recognized buildpacks
Added option to deploy only if tag is present
Merge pull request #18 from Aaron1011/smart_buildpack

Automatically expand URL for recognized buildpacks
Merge pull request #17 from Aaron1011/heroku_tests

Added tests for Heroku Anvil strategy
Merge pull request #19 from Aaron1011/tags_deploy

Added option to deploy only if tag is present