dive site handling

[Berthold Stoeger]

Dear all,

On Friday, 22 February 2019 21:37:18 CET Dirk Hohndel wrote:
> We went through a few painful iterations in the dive site handling and ended
> up on a compromise that few of us really love, many of us actually actively
> dislike and that we really want to get to a better state.

>From the comments so far, it seems to me that there are at least four, 
probably more, not completely independent problem fields.

1) The UI. We want a list of dive sites with add / edit / remove / search 
functionality.

2) Dive site fields. Is one GPS coordinate sufficient?

3) Semantics of editing dive sites. Copy on write?

4) Synchronization of dive sites between distinct dive logs.

Since I was planning on integrating the dive site handling into the undo-
system anyway, I propose that I realize 1) while I'm at it. Since I recently 
replaced dive site UUIDs by pointers I hope that I still have a decent 
overview concerning this part of the code base. But give me a week or two 
(first I want to finish the grunt work of undo of the notes-tab).

For 2) to 4) I'll not interfere, as what we have so far is adequate to me.

Berthold