cmd: Add check for newer config file and an option to override it (fixes #4921) (#5597)
cmd: Add check for newer config file and an option to override it (fixes #4921) (#5597)

* Add check for newer config file and override option

* Expanded error message

* Polish previous commits

* Make it newER

wweich/syncthing,imsodin/syncthing,xduugu/syncthing,imsodin/syncthing,xduugu/syncthing,AudriusButkevicius/syncthing,AudriusButkevicius/syncthing,imsodin/syncthing,imsodin/syncthing,syncthing/syncthing,wweich/syncthing,syncthing/syncthing,AudriusButkevicius/syncthing,imsodin/syncthing,wweich/syncthing,syncthing/syncthing,syncthing/syncthing,xduugu/syncthing,AudriusButkevicius/syncthing,xduugu/syncthing,syncthing/syncthing,wweich/syncthing,syncthing/syncthing