[19/n] DeviceID validation.

Summary:
Full stack:
D2809 D2875 D2752 D2904 D2759 D2760 D2808 D2762 D2876 D2769 D2877 D2807 D2814 D2870 D2888 D2915 D2976 D2977 D2978

deviceID validation by format:
prefix:suffix

prefix - is one of the list: ks, web, mobile
suffix - is a random generated 64 character string

P.S. Allow only one key server ks:256 and reject others.

Linear task ENG-615

Test Plan: Passed a valid string format and got expected true result. Then passed string in wrong format and got a validation error.

Reviewers: karol-bisztyga, palys-swm, ashoat

Reviewed By: karol-bisztyga, palys-swm, ashoat

Subscribers: benschac, ashoat, palys-swm, Adrian, atul, karol-bisztyga

Differential Revision: https://phabricator.ashoat.com/D2978