add a way to restart and reload dcd

[yannick]

• each open window should have its own dcd server on a specific port
• there should be a command to reload all files and update them (e.g. if a new dependency is added to dub.json/dub.sdl)
• there should be a command to completely restart the server e.g. if it has crashed

[WebFreak001]

• Already implemented
• Reloading dub files currently works through Switch Configuration but better way will be added
• Killing the dcd-server and workspace-d process works but I will probably add an easier way for dub too, as the command is already implemented in the D backend (workspace-d)

[WebFreak001]

Fixed in commit d43662c

[WebFreak001]

Nvm still need reload

[WebFreak001]

Requires workspace-d update