Made package go-gettable

This was really a simple change. I simply:

* made a new directory dendrite inside the root of the repo
* moved the main executable to the dendrite folder
* replaced the local import "./src/dendrite" in the main executable with the full github path.
* moved all files in ./src/dendrite to the root of the repo

If you have any questions or comments, please let me know.

Note: I have no idea how your build script works, but I'm guessing this will break it. Sorry about that. If it's an issue you can't easily fix, I can look into it.