BookmarksView: Add the support for bookmarks
Add of the bookmarks view as a new option enabling the user to add a bookmark at the current timestamp of the currently playing media.
The user can also select a bookmark between the bookmarks table, rename and delete one.
This merge request also includes a feature allowing the user to add bookmarks at specific timestamps, so that the user becomes able to add several bookmarks in a row.
Edited by Diogo Simao Marques