…y SQLite specific code

Fix #277

For mp3 files, the "Part Of a Set" tag (`TPOS`) can be either a single
number, or two numbers separated by a '/' [1].

Sonerezh always wanted two numbers separated by a '/', and, for ogg
files, only filled the disc tag if both DISCNUMBER and DISCTOTAL existed.

This fix does two things:
1. For ogg files, DISCTOTAL is now optional
2. Handle both formats, i.e. w/ and w/o '/'

[1] http://id3.org/id3v2.3.0

Detect DISCNUMBER tag without DISCTOTAL

Adding a translation file for German Translation of the web interface

Add German locale

Fix indetation

Fix typo

Fix indent

Applying 4 space coding convention to indentation

Fixes some extra whitespace and some typos

Fixing the rest of extra whitespace

Adding German Translation