0.18.0

Changelog

a99ad8a Add state transitions attribute
3e742d6 Add state transitions docs
566d44d Clarify release tag to use SemVer
91d5d15 Fixing missing libc6-compat in docker image
617fe0f Merge pull request #74 from RaniSputnik/feature/state-transitions
2661a1e Merge pull request #83 from chrisabird/master
0c68d7b Update changelog for 0.18.0
78ba44c Update docs
67dc428 Update resource_state_test.go
4a32939 Update transitions attribute to set from list