iOS: Version string assertion

[piotr-cz]

At this moment for an iOS version, any string may be used, however Apple has specific rules.

Failing to use this format results in error when submitting app from XCode.

Reference: Apple Developer > Documentation > CFBundleShortVersionString:

This key is a user-visible string for the version of the bundle. The required format is three period-separated integers, such as 10.14.1. The string can only contain numeric characters (0-9) and periods.
Each integer provides information about the release in the format [Major].[Minor].[Patch]

I've been using SemVer like 1.0.0-beta.3, before I found out (the hard way) that specific format is required.

My idea is to assert ios.version with a regex and when it fails, exit trapezedev with a handy notice such as Supplied version doesn't match Apple requirements: [Major].[Minor].[Patch]