Adds definitions and tests for the Mousetrap global-bind extension
Modified Mousetrap definition to allow Mousetrap to be loaded as an
external module.

- tests are also updated to test loading as an external module
- mousetrap exports itself as an AMD module when an AMD define function is
  present
Merge branch 'master' of github.com:cspotcode/DefinitelyTyped into cspotcode-master
mv mousetrap-global-bind/mousetrap-global-bind.d.ts -> mousetrap/mousetrap-global-bind.d.ts
Merge branch 'cspotcode-master'