Create itel_journal_german.csl

The Citation Style for the iTeL-Journal.
Update and rename itel_journal_german.csl to interdisziplinare-zeitschrift-fur-technologie-und-lernen.csl
ID renamed to interdisziplinare-zeitschrift-fur-technologie-und-lernen
removed umlaute and locale section
Merge pull request #795 from cfertl/patch-1

Create itel_journal_german.csl