Added more warnings and put them under the new heading "Important
Caveats".

In preparation of possible Gitlab pages hosting.

It's too big!

Ugly but functional. Needs more tidying.

Also renamed `GeocachingGamePlugin` namespace to
`GeocachingAndroidPlugin` to prevent clashes.

Trying to make it clear what is part of the demo and what is required
for the plugin.

Also an update to the README and the removal of some unused files.

Aka "Create base plugin integration"

Also, let this be a lesson to myself to always backup my repos.

Hopefully caching information rather than calculating it every frame
will help a little with frame drops.

Based off MapzenGo: https://github.com/brnkhy/MapzenGo

Customized `DynamicTileManager` script to be properly centered on
player in a way that is easier (for me) to understand.

Basically making sure everything works at the most basic level.

* Check that data can be sent from Android -> Unity
* Check that map data is correct using Mapzen

Contains empty Unity project with Unity Test tools and default Android
Studio project.