[pull request]: dive details rework

[Sebastian Kügler]

Please pull from git at github.com:sebasje/subsurface.git 
branch "divedetailssplit".

The plan was to split up viewing and editing the dives in order to make 
both modes work better for their purpose. (For example, we don't need the huge 
profile picture in the edit mode, since it can't be edited, anway.)

This set of changes implements that. it puts the actions between viewing and 
editing into a right-hand-side drawer. You will now see the lower button 
having two arrows in the dive details view, and you can also draw the the left 
to reveal the right panel. This one holds contextual actions for the dive. 
(The left-hand-side panel is the global menu of the app.)

I'm not sure if that's discoverable enough, though, but would like feedback on 
the approach. If it turns out to not be discoverable enough, I'll feed this 
info back to the usability and designers, and we'll put the actions in the top 
toolbar.

Saving the new dive data has broken right now in master, and this patch-set 
unfortunately doesn't change that. Something we have to look into.

Cheers,
-- 
sebas

Sebastian Kügler    |    http://vizZzion.org    |     http://kde.org