Allow to create archive with difference between 2 revisions

#1361
Allow to create archive with revision filter from Menu

#1361
Archive revision's checkbox shouldn't be checked if there is only one revision
rearranged layout
Uncheck Revision path checkbox or revision diff checkbox when checking the other one.

Hide diff commit summary control
- Removed sort on selected revision

- Change commit summary to a small one
Check if focus is where it was initially. Fixes #1899.
move user manual handling out of UI
move open in default browser functionality out of UI
Merge branch 'pr/n1918_mexx'
Corrected URIs
Removed compiler warnings.
DeleteUnusedBranchesForm: add Settings button to directly go to corresponding plugin settings page
DeleteUnusedBranchesForm: set minimum size for dialog
BackgroundFetchPlugin: if invoked via menu show SettingsDialog instead of doing nothing
rearrange layout
Added likn to wiki page
Fix #1660: replace GitEx with GitExt
replace gitex with gitext in LinkFactory
Merge pull request #1925 from feinstaub/feature/goto_plugin_settings

Open corresponding SettingsPage directly from Plugin