Add explanatory text in empty sourcelist and timeline
@bilboed
Submitted by Edward Hervey Assigned to Edward Hervey @bilboed
Description
It is not obvious what people should do when they start PiTiVi if they want to actually start working.
Adding some text in the empty source-list and timeline explaining what people should do would help with that.
Ex:
SourceList : Click on 'Add' to add files to be used in the Timeline
Timeline: Drag your sources here
Ideas on better texts are welcome.
Imported from https://bugzilla.gnome.org/show_bug.cgi?id=383402