UX: throw error about `ios-deploy` not being installed earlier in the process

[lucasbento]

Describe the Feature

For some reason I always get errors with ios-deploy not being installed so I have to install it again, right now I have to go through these steps to know that it's not installed:

• Run run-ios with --device argument;
• Wait a few minutes for the build;
• See the error;
• Install ios-deploy;
• Rerun run-ios.

This could be improved to show the error to the user as soon as it sees that the --device argument is fulfilled and there's no ios-deploy.

Possible Implementations

Run which ios-deploy as soon as it sees that there's a --device or a --udid that matches a device, if it outputs something continue, throw the error if not.

[thymikee]

Sounds like a nice improvement!

[lucasbento]

I'll work on this later on this week.