Webservice: only mark divelist changed if we actually modified it

If no new gps fixes or new location names were obtained from the
webservice there is no need to save the datafile on exit.

Reported-by: Sergey Starosek <sergey.starosek@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Recognize another name for auto created fixes from companion app

We need to have this be one well defined string -> this requires a change
to the companion app as well.

This commit also hides the (untranslated) debug message if no dives in the
dive table match a gpsfix downloaded from the webservice.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Don't duplicate gpsfixes if downloading them multiple times

Simply clear out the table (and free the "dives" that were created).

Reported-by: Sergey Starosek <sergey.starosek@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>