Merge branch 'develop'
Update README
Merge branch 'develop' (v0.4.0-beta)
Merge branch 'develop' (v0.4.1-beta)
Update app version (v0.5.0)
Add PDF content handling

Use PDF extraction as an external web service.
Update README.md

Added v0.5
Update README.md
Move submodules to app/lib and appver to settings.
Merge branch 'master' into develop

Conflicts:
	app/.env
	app/lib/ebooklib
	app/lib/pyphen
	app/lib/readability