Merge branch 'master' into gh-pages

# By Scott Jehl (7) and Mat Marquis (2)
# Via Mat Marquis
* master:
  Simplified `sizes` example.
  update project version
  update bower version and pointer
  update authors list
  updated demo page to prep for beta (links and text)
  Ref. #207 - Ignore non-`source` elements while parsing `picture` internals, halt upon encountering an `img`.
  winning length must be non-zero. fixes #190
  simplified some logic when no length is found
  code style consistency

Conflicts:
	dist/picturefill.js