Initial version

The goal for the initial version is to have a basic working switch.
At this stage it is not my goal to implement any of the protocol extensions yet.

This version should support the following features:

- crypto
- line management
- channel management
- DHT, peer management
- application level channel API
- compatibility with the Node implementation

To do list:

- [ ] improve packet acking
- [ ] broken line detection
- [ ] broken channel detection
- [ ] clean shutdown