Propagating changes from code.google.com(https://codereview.appspot.com/13536043/).
This is a refactoring to support the addition of another script
needed in the code.google.com repository but not needed in i18n.
Merge remote-tracking branch 'codedotorg/mooc' into i18n
Removed out-of-date translation files.
Merge pull request #29 from nanan9177/mooc

Removed all of the interstitials in Maze mode 2.
Maze starting direction
Karel starting direction
Merge pull request #32 from brandonbloom/start-dir

Start directions for Maze & Karel
Removed obsolete function displayInterstitialOrCloseModalDialog from common.js and turtle/maze (removed from everywhere).
Added relative width and margin video attributes so video stays confined to the modal dialog.
Merge pull request #30 from nanan9177/mooc

Added obstacles for mouse and cheese in Maze
Merge pull request #33 from brokenairplane/mooc

Removed obsolete function displayInterstitialOrCloseModalDialog from common.js and maze/turtle templates.
Updating generateXMLForBlocks in common.js to be more readable.
Convert levels form structure of arrays to array of strucures.
Applied Ellen's feedback and added in another variable to add height to the iframe at a slower rate than the blockYPadding.
Merge pull request #34 from brokenairplane/mooc

Updating generateXMLForBlocks in common.js to be more readable.
Merge pull request #41 from brandonbloom/soa2aos

Convert levels form structure of arrays to array of strucures.
Removed TODOs from template and cleaned up the text. More to do after Ellen's CL that moves common messages. Pushing this to avoid merge conflicts, and have maze/template.soy better prepared for final changes.
Merge pull request #43 from brokenairplane/mooc

Removed TODOs from template and cleaned up the text.
Array of structures: Part 2 (maze.js)
Remove trailing commas