Lute v3

Feature changes:

• Add .epub import (feature 19). By @sakolkar in #82.
• Add resize frame option in reading pane. By @webofpies in #77.
• Add “dismiss” demo option, for users who don’t want to wipe the db. By @dgc08 in #80.
• Nicer styling for the reading menu. By @webofpies in #72.
• Add Hindi and example to baseline. By @mzraly in #76.
• Update German sample story to new orthography. By @dgc08 in #81.

Back end changes:

• Fix javascript attribute names to standard. By @robby1066 in #79.
• Fix GitHub CI to really fail when things fail.
• Restructure book service to support epub import.