refactor: deprecate EdcSetting, add Setting

[paullatzelsperger]

What this PR changes/adds

Deprecates the @EdcSetting and @EdcSettingContext annotations, and introduces a new @Setting and @SettingContext annotations, both of which are exact copies of the old thing.

Why it does that

To keep consistent with the naming of all other metamodel annotations.

Further notes

We need to do the deprecation and removing in two separate steps, otherwise there could be a time where builds in downstream projects fail, until the make the switch as well.

Linked Issue(s)

Closes #19

Checklist

• added appropriate tests?
• performed checkstyle check locally?
• added/updated copyright headers?
• documented public classes/methods?
• added/updated relevant documentation?
• assigned appropriate label? (exclude from changelog with label no-changelog)
• formatted title correctly? (take a look at the CONTRIBUTING and styleguide for details)