Update editor_edit.txt

Update delete_intro.txt

Update assignments_intro.txt

typo

Create settings.php

FRENCH language file

Create lang.php

Create editor_intro.txt

Create editor_edit.txt

Create delete_intro.txt

Create assignments_intro.txt

translation update

Skip undefined schemas

Fixes GitHub #107 and Jira SPR-503

Utilize StructException's translation handling

Use existing exception instead of new msg handling

Localize error message

Show error-message if schema does not exist

That way it is more clear where the problem lies and what to do.

SPR-501

Version upped

Use last file in config cascade

This last file is the one actually used to determine whether the cache
is still valid. DOKU_CONF . 'local.php' is not necessarily part of that
cascade

Invalidate the cache when a schema changes

So Schema changes are visibly immediately.

SPR-347

Check schema_assignments.tbl in aggregation

This check has most likely just been forgotten.

SPR-450

Ensure that struct output is only rendered once

SPR-491

Add tests

SPR-466

Fix sorting by a multi column

A multicolumn is always sorted by its first value which is already copied
to the respective column in the table.

SPR-466

translation update