[CLI] Manual watching the source changes

From @raffaeler on February 6, 2019 10:58

Is your feature request related to a problem? Please describe.
When tns run is started, it takes a while before deploying the application. For this reason I prefer to run in watch mode (tns run or tns debug).
Anyway, when you are doing more than a trivial change, it would be useful to manually trigger the compilation/deploy without stopping and re-running tns run or tns debug.

Describe the solution you'd like
When the terminal is in tns run or tns debug it can accept keyboard commands. It would be useful to add support for three commands while the terminal is watching:

• 's' key: suspend watching
• 'r' key: resume watching
• 'd' key: deploy while in suspended mode

Describe alternatives you've considered
Stopping and restarting tns run or tns debug is way too slow.

Copied from original issue: NativeScript/NativeScript#6865

Commencez par les points d’entrée de la CLI pour tns run et tns debug, en vous concentrant sur leur cycle de vie en mode watch et sur la gestion des entrées du terminal. Définissez comment doivent interagir la surveillance suspendue, la surveillance reprise et le déploiement manuel, puis vérifiez que les commandes demandées s, r et d fonctionnent sans arrêter la commande en cours d’exécution.