[BUGFIX] Make WelcomeController compatible with SQLite

See merge request !2

[CLEANUP] Remove dead code in StartController

See merge request !1

Add links to legal notice and privacy policy

See merge request !3

Upgrade Redmine to v4.1

[BUGFIX] update feed template to prevent exception during url_for call

Adds in changes from redmine that fix the parameter handling

The WelcomeControllerPatch uses MySQL 'RAND()' function to get a
random user. This is incompatible with SQLite, which might be
a comfortable alternative during testing.

To allow using SQLite, use 'RANDOM()' instead, if the DB adapter
is 'sqlite3'.

This code is never used, but that from
`lib/welcome_controller_patch.rb` instead.

Thus, remove it.

based on https://raw.githubusercontent.com/jkraemer/redmine_percent_done/

[TASK] Show a note about LDAP on login failure

Our old Redmine installation has these fields already.

I think this is still needed...

Use the new plugin name `typo3_forge`