Use _.pick where possible
Use specified rather than computed property values
Point bookmarklet to experimental code
Start style search all the way at html tag
Zero is falsey, so check for undefined explicitly
Bookmarklet should start at document head
Abbreviate background properties
Avoid unsavory nodes inside head tag
Update tests to reflect new way of calculating
Use specfied rather than computed values. Fixes #8

* specified_values:
  Update tests to reflect new way of calculating
  Avoid unsavory nodes inside head tag
  Abbreviate background properties
  Bookmarklet should start at document head
  Zero is falsey, so check for undefined explicitly
  Start style search all the way at html tag
  Point bookmarklet to experimental code
  Use specified rather than computed property values
  Use _.pick where possible