first try on new next/prev
many bug fixes and accuracy improvements for iteration
Talmud and Talmud Commentary iteration
Merge branch 'master' into next_prev_ref
Merge branch 'master' into next_prev_ref

Conflicts:
	reader/views.py
ToC - link to first available text vs head of section.
fix to talmud index formula?
minor fix
Merge branch 'master' into next_prev_ref
small comments add
Bandaid fix for metrics script
Fix bandaid
Port Notifications to Sefaria Abstract
Notifications for Discussion notes
Merge branch 'master' into refactor
Fix import path
fix import paths
Move text.py exceptions to a Unicode base.  Deprecate % usage in favor of .format()
Allow Sheet Collaborators (can add) to reorder
Add nav to splash