Create branch
Initial refactoring
QA: factorize trw_layer_acquire* functions

The module viktrwlayer is really huge. Any factorisation seems good,
even really small like this.

Furthermore, such minor refactoring would probably help to find
a more significant refactoring.
Merge commit 'refs/top-bases/t/export/extract-export-module' into t/export/extract-export-module
List for translations
Improve test util
Change branch deps
Merge commit 'refs/top-bases/t/export/gpsbabel' into t/export/gpsbabel

Conflicts:
	src/viktrwlayer.c
	src/viktrwlayer_export.c
	src/viktrwlayer_export.h
Normalize calls
Update
Merge commit 'refs/top-bases/t/export/gpsbabel' into t/export/gpsbabel
Fix the display of speed in statusbar output.
SF Bugs #104: Fix GStatBuf not available on Glib < 2.26
[QA] Remove build references to things that don't exist anymore.
Update spec file
Move man files from doc to help directory so they will be included in the output from make distcheck.
Refactor: passed around aggregate menu values
Refactor: passed around map layer menu values
Only the TrackWaypoint layer should handle it's internal callback type.
Remove never used GPS layer drag drop request function.

Seemingly never used and it's not clear what it was meant to achieve.
Even if it was invoked, it would have aborted the program anyway:
 as it was the only user of vik_gps_layer_delete()
 which would have failed on the number of disconnect signals never equalling 1.

So remove vik_gps_layer_delete() too.