Merge pull request #244 from nanan9177/tutorial

Changed level 8 and 10 so that they are less repetitive.
Use assetUrl function instead of baseUrl string
release 0.0.33
Merge pull request #246 from nanan9177/tutorial

One star feedback
Merge pull request #245 from brandonbloom/cdn

Use assetUrl function instead of baseUrl string
release 0.0.34
Incorporate 99d584d from blockly-core
release 0.0.35
Updated Karel Levels' maps.
Add LICENSE and NOTICE files
Merge pull request #249 from nanan9177/blockly_fix

Updated Karel Levels' maps.
Fix feedback null check in dev
Blockly-core 7242673
release 0.0.36
Updated angry birds sound effects to use official sounds.
Updated Farmer night background.
New Angry birds images.
Updated angry birds images and animations.
WIP. New Angry birds animations.
removed 2 unused strings from Maze.