Refactoring keys package #196
Added some tests showing the expectations of how should keybindings
work after supporting parent child hierarchy.
Key-bindings parent child support closes #196
Loading all keybindings in proper order
Merge branch 'master' of github.com:limetext/lime into iss196

* 'master' of github.com:limetext/lime:
  Fix more "Print"s that should be test errors
  Make errors fail tests rather than just output
  Run `gofmt` on util tests
  Add section 5: "If you'd like to help but don't know how"
  Expanded test suite for the util package in Lime Text submitted by schallert, jchoi1, lindzy, shuaisha, & dingty.
  Improve CONTRIBUTING.md.
  fix typo
  Clarify CONTRIBUTING.md
  implemented select keybindings for shift+arrow
  Replace BufferChangedCallbacks to BufferObservers in frontend code (#427)
  Resolve #25: Implement the find_next command
Change keyOff name to seqIndex
No need to extra variable r
Merge pull request #463 from zidoms/iss196

Key-bindings "parent, child" support