Fix tabtab for -- options

Add IOptionsService interface with one method - getKnownOptions. This method is used in commands service in order to get full list of supported -- options. As each CLI have its own list of knownOptions and the mobile lib has only some of them, the implementation of the interface has to be outside of the lib. This way we can use autocomplete for all available options, not only for the common ones.
Merge pull request #100 from telerik/vladimirov/fix-tabtab-for-options

Fix tabtab for -- options
Validate iOS appstore commands

Use iTunes validation for appstore commands. Add IiTunesValidator interface with a single method - getError. Chang ITunesValidator class to implement this interface and move the class to new file. Use the implementation to validate appstore list and appstore upload commands.
The validator is required when you are using x64 bit Node on Windows - in this case we are unable to use iTunes as it doesn't have x64 bit dlls.