Update view to support learning progress for free text



See merge request !4

Add migration which converts database and LDAP UIDs to lowercase

ARSnova Backend now converts all user IDs for database user accounts to
lowercase. This migration converts existing accounts for compatibility.
Documents mapped to LDAP UIDs are also reassigned to lowercase UIDs
since most LDAP configurations use case-insesitive comparison for UIDs.

This change was done to prevent duplicate account creation.

See merge request !3

ARSnova Backend now converts all user IDs for database user accounts to
lowercase. This migration converts existing accounts for compatibility.
Documents mapped to LDAP UIDs are also reassigned to lowercase UIDs
since most LDAP configurations use case-insesitive comparison for UIDs.

This change was done to prevent duplicate account creation.

Motd

Message of the day feature:  
An in the properties defined adminaccount can create a MotD that can has the audiences "students","tutors" or "all". e.g.: If you define a motd's audience as all, it will be shown on the FrontPage of ARSnova. A Message has start- & enddate to define the timerange, a title and a text which can be formatted via markdown.

See merge request !2

sort public pool sessions by subject and then name

https://scm.thm.de/redmine/issues/17140

view for public pool by subject is modified to sort sessions by subject and then by name.

See merge request !1

Merge branch 'Feature#14773' of scm.thm.de:arsnova/swtp2015-text-checker-setuptool into Feature#14773

Merge branch 'Feature#14773' of scm.thm.de:arsnova/swtp2015-text-checker-setuptool into Feature#14773