tika updaten

:construction: 
A new version of tika has been released. Since switch.ch removes old versions after quite short time we have to upgrade it.
- [x] Analyse changelog. Check new features etc.

https://tika.apache.org/1.5/index.html
Mostly bugfixes, small features and new versions of dependencies.
The multipart/form-data support and NonSequentialPDFParser are interesting.
- [x] Update version in package
- [x] Test the conversion

Tested by comparing the parsed output of a pdf before and after the update (with and without server).
Everything stayed the same. Tests passed.

@lukasgraf