Draft: Labgrid test

Added the labgrid_test rule

This rule uses a number of other rules and targets to accomplish what it needs to do, in summary it: Uses the executor to setup the labgrid environment on the host, and executes the labgrid_test run.py inside of it.

The run.py takes the two binaries(test_runner and a binary) as arguments and transfers them across to the device before finally running them.

run.py takes the test runner written in go which then executes the test_binary on the device.

Essentially the commands are ran in this order, each of them passed as parameters to the previous.

host         host     device        device
executor.py->run.py->test_runner->test_binary

To run cd into e2e/ and run:

bazel test //docker:simple_test