[repos] cosmetics: use temporary variable for the add-on being processed
[repos] update the broken status only if we don't have a newer add-on installed (or in the database)
[repos] cosmetics: indenting
[repos] process only the most up to date version of add-ons across all repositories
Merge pull request #3878 from jmarshallnz/more_dep_checks

Check versions when marking as broken - no point marking old versions as broken when new versions exist