License for this library

[bbailleux]

Hello dear author,
in order to use flutter_google_map_view component, it is important to know its license to avoid any legal risk.
Can you add at least the name of the chosen license in the LICENSE file ?

[benbrittain]

This is also something I care about. I'd like to suggest BSD 3-clause, MIT, or Apache 2.0.

edit: It's now MIT apparently. Thank you!

[matthewtsmith]

Added MIT license