split SceneEditor fragmetns into their own standalone classes so we can use them from 2 different activities
cleanup unused imports
refactor db for multi scene projects; hack existing editors to use new db schema
alter template json format to support multiple scenes; update asset loaders to new format
fixed lesson loading bug
add "supports righ-to-left" flag in manifest
added video 3 scene for arabic
fixes for indicate scene idx to use for scene editor
Merge branch 'multi-scene-refactor'