Bring back ch06 as it has needed details we need to flesh out.

This reverts commit 526e8e6d.

Gateware design overview and version retrieval

See merge request beaglev-fire/docs!1

Add BeagleV-Fire and librobotcontrol

See merge request docs/docs.beagleboard.io!66

Updated contributing guide

See merge request docs/docs.beagleboard.io!65

```shell-session
$ source ./venv-build-env.sh
$ cd projects/librobotcontrol/docs
$ doxygen
$ cd ../../..
$ sphinx-build -M html . public
```