Blockly changes for jigsaw

Skip over all the i18n stuff to get to the meat of things.

A new app to familiarize young kids with dragging and dropping blocks.  For each level, we'll take an image, and split it into some number of blocks.  We'll either present a workspace with no toolbox and the blocks inside of it, or have the blocks in the toolbox.  You complete the puzzle by correctly putting the blocks together in the workspace.

Images are put on the blocks by creating an svg pattern, and then setting the fill on the block.