Fix file name of PDFs

[emilianoricciardi]

No description provided.

[craigsapp]

Done. Now the filename will be the catalog number. The title, composer and publication date should also be added. This information would need to come from the list of files stored on github, or from an entry in the settings index files which lists the filename that should be used.

For example Trm0047m.pdf would use the original title of Trm0047m-Non_e_questa_la_mano--Giovannelli_1588.pdf found in the name of the source file:

https://github.com/TassoInMusicProject/tasso-scores/blob/master/Trm/kern/Trm0047m-Non_e_questa_la_mano--Giovannelli_1588.krn