fixes #1794 Rename of app ensure name is unique

Fixes #1794

STR:
1. create a new app, name it something.
2. create another new app, and name it something else.
3. open project menu, and change the second apps name to the first.

Expected: Should not let you save it.
Actual: It makes a dupe of the project in your user menu both pointing to the same project.

STR:
1. new app
2. save it, name it something.
3. rename it using the title at the top of the phone's UI.

Expected: the original name should no longer be a thing. Should just have one project, saved over the last. I changed the name.
Actual: it did a fork and I now have a project saved at the point of the rename.
actually, this file mixes appName and appDescription, which is what we've defined as attributes, but then we use app.name and app.description in the JS instead (maybe we didn't catch that when we first landed it?).