Add cellTail

[mousetail]

CellTail is a pretty unique esolang:

• Based on cellular automata which is rare
• Pattern matching based syntax
• Requires a very different approach to solving problems than most esolangs which are mostly either tape or stack based

[angrykoala]

Hi @mousetail Thanks for the PR. To make reviewing simpler and keep better track of additions, would you mind splitting this PR into 2 separate PRs? One for each language

Thanks

[mousetail]

@angrykoala done