Alternative highlighting style for users with low vision
Version 1.30.2
Fix possible NPEs
Jump over past lectures in list also in onResume()
Favorites list: Ask for confirmation before deleting all favorites
Hide delete action if favorites list is empty.

Hack: Pass confirmation dialog ID back to listener to
differentiate between different dialogs in one acitivity. Better solution
would be to pass a listener to the DialogFragment, but those cannot
be put into a bundle via setArguments. :-/
Fix successful return from XML parser with missing closing tag
bump version to 1.30.3
Update Gradle plugin to v.2.2.
Add configuration for Travis-CI.

+ Add signing configurations for ccc30c3 & ccc31c3 flavors
  to gradle.properties.