Add a LICENSE.md file to the repository

[patrickjameslawrence]

Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

• I'm frustrated that this repository isn't legally licensed.
  Describe the solution you'd like
  A clear and concise description of what you want to happen.
• Add a license file to the repository.
  Describe alternatives you've considered
  A clear and concise description of any alternative solutions or features you've considered.
• None
  Additional context
  Add any other context or screenshots about the feature request here.