[Process] Added support for processes that need a TTY to run.

Added support for processes that need a TTY to run. This can be useful in scenarios where we need to open an editor and wait for the user (like "crontab -e" or "git commit"). The new methos "setTTY" can be used to control this.

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | 
| License       | MIT
| Doc PR        |