Gemification

Kiwano is now a Gem. To install locally, checkout this branch, then
```
rake install
```
You may need to bundle first.

That should create a pkg directory. Run 
```
kiwano example.json
```
and Kiwano should fire up. 

I've had to restructure the project a fair bit so merging in other branches that were taken before this one will be a bit of a faff.