Merge pull request #1 from Nevraeka/master

Monkey patch register -> registerElement
Use only one function call
Simplify document.registerElement aliasing, also use the same code style as in the rest of the patch
[documentation] Updated info for element registration

Description:
  Updated documentaion for custom element registration
  monkey patch.
Merge branch 'master' of https://github.com/Nevraeka/WebComponentsMonkeyPatch