Locale compare

This fixes the sorting issues with umlauts on Ubuntu. 
It registers a custom collation function directly to sqlite. 
This will only work, if the libsqlite shares the same version with the sqlite implementation in Qt. 

To fix the search issue, we need to override the "LIKE" operator. 

Clementine has used this solution as well, but it was removed from the source. I have not figured out why.  
This method is only defined if __SQLITE3__ so I think this will fail to compile with localecompare=0.