Implemented Edit and Delete

Basic capabilities working

To View Manga in a expandable list view
-Parent List shows Title
--Child list shows last book and ongoing or completed

Add Manga
-User is able to add a new manga with Title, Last Book, and Status

Edit
-User is able to edit an existing manga with Title, Last Book, and
Status

Delete
-User is able to delete an existing manga with confirmation

More TODO
- Button on the mainActivity needs to increment the last book by 1
- Add a favourites boolean to Manga
- Implement tabs to support All, Completed, Ongoing, Favourited
- Implement a search-filter
- Finding out what other attributes a Manga should have
- Implementing of associations with pictures to put as background for
manga