Boismortier header consistency fix

Fix mutopiatitle to match piece name
Fix partial warning in Sonate 2, 3, & 4

I started to create a simple issue to discuss these edits but decided I would make the changes and pull request and it can be rejected if considered inappropriate.

The problem is that the `mutopiatitle` field in all 4 pieces had an embedded carriage return which caused them to be ignored in our compilation software. What got picked up for the title was the value in the `piece` field. My change makes the piece match our RDF, and thus other page output, so this update can be made without a recompilation. (The partial fixes remove the warnings but the pdf output matches the original.)

However, it may be that the author wanted the title shown in Mutopia to be the original `mutopiatitle` so I have corrected the format of the line and then commented it out.

Again, if this is not correct simply reject the request and make the appropriate repair.