How to hide running app from Dock in Yosemite? I want to hide icon of running app in Dock without installing any apps like Dockless. Maybe there is some CLI unix trick.

This Info.plist trick does it but modern Code Signed apps don't work:

Hide a running app from Dock?
The plist edit should work with Signed Apps, you just might need to force a resign. Try the command sudo codesign -f -s - /path_to_app/appname.app, replacing appname with the name of the app you are looking to hide from the dock.

Note that this will also disable menu bar actions, but all keyboard shortcuts should still work.