Add "no-run" option

Hi!

The command `ionic cordova run ios --livereload` uses by-default `native-run`

In my particular case I don't want automatically start a simulator nor auto run the app in any connected device. I would rather like to run the app with XCode myself.

That's why I suggest to add a `no-run` option which will not run anything automatically.

Start at the `ionic cordova run ios --livereload` command and inspect how its options lead to the automatic `native-run` invocation. Add the `no-run` option so the app is not launched in a simulator or connected device, then verify that the normal run behavior remains unchanged without the option.

Written by the indexing model from the issue text.