Added CKEditor 4.3.1 standard.
Merge branch '4.3.x/standard' of github.com:NYPL/ckeditor-releases into 4.3.x/standard

* '4.3.x/standard' of github.com:NYPL/ckeditor-releases:
  small test commit
  minor edits to config.js and change of dir for image2 images
  add image2, lineutils, and widget plugins
Testing making the figure element editable for linking it.