Handling of psalm titles across formats can be improved

[schierlm]

It seems that every format has its own conventions how to treat Psalm titles (Descriptitve Titles).
Some formats have their own tags or formatting directives for them, other put them in verse 0 or title, other append a /t to the verse number.

Some of the migrations have been implemented in BibleMultiConverter, however not consistently (so it does not work from every format to every other format).

Therefore, all formats should be checked how they handle Psalm titles, and then decided how it should be handled in the intermediate format. Then all formats should be updated accordingly.