Add terminal: Cool Retro Term

[mblarsen]

Checklist for submitting a pull request to Terminals Are Sexy:

• [x] I have carefully read and comply with the Contributing Guidelines of this repo.
• [x] I have searched the PRs of this repo and believe that this is not a duplicate.

• Title: Cool Retro Term
• Link: https://github.com/Swordfish90/cool-retro-term
• Category: Terminal Emulation Applications
• Description: Emulator of terminals of old. Makes your terminal look like an Apple ][ or IBM DOS.

This list cannot be considered complete without this entry :D