Further improvements to the Score Wizard

[bmjcode]

Hi there! I've made a few more improvements to the Score Wizard:

• Made the MIDI instrument user-selectable for several keyboard and guitar part types
• Added new part types for steelpan (steel drums) and dulcimer
• Added a special "Structure" type for laying out breaks, bar lines, etc. separately from musical content
• Made various small fixes and corrections

[fedelibre]

@bmjcode Could you please remove the fix typo commit from this PR? You may do a new PR containing only the modifications to .py and .dic file. Do not touch the .pot and .po files, as these are normally handled separately when we are closer to a release.

Then I may test your branch and comment on the features you added. I can't review the code, but maybe others will as soon as you remove that commit and rebase on current master.

Sorry for the long delay, but as you can see from the history Frescobaldi development is slowly coming back. We'd like to release 3.3 soon, after fixing the last critical issue.

[fedelibre]

@bmjcode I did the cleanup for you and force-pushed to your branch.
I'll test it as soon as I have some time.

[fedelibre]

I've now tested it and it looks good. Waiting for others to give feedback on code.

[dliessi]

The changes look good to me and seem to work as expected.

There is a merge commit in the history, which is undesirable. @bmjcode Can you please rebase your branch on origin/master and push again? (Next time you may use a new branch for submitting changes, instead of master.) Thanks.

Marking my review as "Request changes" for the rebasing, otherwise I approve it.

[bmjcode]

@dliessi I'll be happy to if you can tell me how to do it. My understanding of Git is frankly pretty limited.

[fedelibre]

It's more difficult now that you've rebased on master and your commits are way down the list. I would have squashed them first and then rebased on master.
I would wait for suggestions from Davide and Jean, who are more competent than me.

My suggestion is making a backup branch first:

git checkout -b 1375-backup

Then change back to the branch of this PR and try fixing the commits:

git checkout master
git rebase -i 36d7a38b4db25c608958da08f289268dd8dd1ae1

where that committish is the first commit in this PR.

If you're not confident on rebasing you may leave this task to Jean.

[jeanas]

Now rebased and merged (based on @dliessi's review; I didn't re-review thoroughly myself). Thank you!

[bmjcode]

Cool. Thanks all for your help and patience with this. I have a couple other things I'd like to work on, but they're a bit more complicated. I'll open issues for those so we can talk through the details first.