[Feature Request] Option to hide new note button

[Arty2]

As it stands, the "new note button" is the only button that cannot be hidden. It would be great to have such an option.

Taking the opportunity to say thank you for keeping this tiny gem up to date and featureful!

[Mikescher]

seems simple enough, will add a property in the theme files.

Or, because all the other "hide button x" options are in the SettingsWindow (not in the themes), I'll add it there