Clean up and DRY typealiases.ps1
Clean up and DRY typealiases.ps1

This file is >60% repeated code, making it almost unreadable.

Splitting the type accelerator mappings out into a separate data structure should make the script easier to maintain
kozloski/dbatools,SirCaptainMitch/dbatools,wsmelton/dbatools,dsolodow/dbatools,sqlpadawan/dbatools,Splaxi/dbatools