Better Handling of Multiple Languages

[SalinatedCoffee]

Current language handling is very rudimentary, only checking for exact string matches to identify a language.
Here's a non-exhaustive list of enhancements that should be considered:

• Support for shorthands when specifying language (eg. py3 for Python3)
• Support for adding new language to previously solved problem
• Support for specifying whether to copy readme template or not