introduced auto option for synthetic spread in settings dialog
support for rendition layout and rendition flow properties
introduced separear isSyntheticSpreadDouble and isSyntheticSpreadSingle to settings
introduced named values for scroll and syntheticSpreade settings froperties
Settings dialog cleanup
updated dependency
Merge branch 'develop' into feature/rendition_selection

Conflicts:
	lib/Readium.js
Merge branch 'feature/rendition_selection' into develop
updated dependency