Add "Change File Title" to Context Menu & Delete Comments

[DanielLaube]

Hey guys, 

i am getting started with alfresco and want to do two (seemingly) simple changes:

1. Beeing able to delete comments from the content-app sidebar.
   I think I need to modify the Node Comments Component and the 
   Node Comments service, corrent?
   
   
2. Add a "Change Filename" in the context menu. Do I need to create some custom component alltogether, or is this just something I can add to the "contextMenu" in the app.extensions.json?

I appreaciate every hint!

Thanks, Daniel