[Feature request] Create and edit songs

[rafaeljohansen]

Story

As a Worship Leader, I need to be able to create and edit songs directly in the app. My suggestion for a clean solution would be to provide the ability to add and edit songs directly in the favorite list (.OSZ file), not necessarily in the main song list (local version of the songs.sqlite database). If it is possible to make the favorite list a direct "front end" interface for the "back end" .OSZ file stored locally (and pushed to Dropbox if "live-shared"), then we could have complete freedom to edit and add new songs here.

Conditions of Acceptance

• User should be able to create new songs (that are not present in the main song list) to the favorite list. In the act of creating a new song the user should be able to write the lyrics, insert chords, key and other data (like title) to the song.
• User should be able to edit lyrics, chords, key and other data (like title) to songs in the favorite list.
• User should be presented with a smartphone-friendly GUI for editing.

Scenarios

Scenario 1

• First the user adds songs from the main song list to the favorite list, the songs are copied from the songs.sqlite DB to the .OSZ file. The user also creates a new song from scratch in the favorite list that is directly saved in the .OSZ file.
• Then the user makes some corrections to a song and adds chords and key to another song in the favorite list - everything is directly updated in the .OSZ file - viewable for the whole worship team (if "live-shared" through e.g. Dropbox). (However, the remote songs.sqlite DB is yet not reflecting these changes)
• Finally, sunday morning the user imports this .OSZ file to the OpenLP desktop and pushes the changes to the remote songs.sqlite DB. So know the new song, the corrections and added chords/keys made in the favorite list are seen in the main song list when tapping "Update songs" in the app.

Originally posted by @rafaeljohansen in #549

[sskjames]

Hi @rafaeljohansen, thank you very much for taking time to put a very detailed and beautiful description of the feature. We are actively discussing about all the new features requested.