move project specific files out of this repo and create launch files in twins-controller (twins-controller#5)

work towards simultaneously bringup, old bringup still works (twins-controller#5)

different files for launching the two robots with different topic names (twins-controller#5)

Adds a velocity interface to the driver.

Otherwise the robot would move for too long when handing back control
in the middle of a motion

Do it for all robots

Otherwise speed will return to 0 before a new command gets executed.

TODO:
 - Documentation of function members
 - Using enums for control modes

When robot is already in the target mode (safety- and robot mode) and the set_mode
action is called with requesting to start the program afterwards, the program
did not start as the robot already was at the desired state.
However, e.g. after a protective stop that is resolved by hand (e.g. when driving
into joint limits) users expected to call that action to restart the robot
again.

With this change, we do the usual check whether to start the program again.
This way, this action can always be used to make sure the robot is running with
the program correctly.

Close all closable sockets

Sockets do not necessarily have to be in state connected when they should be
closed. Before, only connected sockets got closed leading to a "socket leak"
if a socket was disconnected before a close request was processed.

With this fix all sockets with a valid file descriptor get closed when close()
is being called.

* added parameters for servoj_gain and servoj_lookahead_time

* changing to ros_error_stream

* lint

* added documentation

Added documentation for non_blocking_read parameter

I almost posted an issue about this problem too, so I suggest noting in the documentation. I didn't expect it to be this easy, and it's probably worth pointing it out.

Users can still customise the publish_rate by removing the alias and specifying a custom rate.

By default all controllers will publish at the controller's native rate.

update our master

Adds parameters for reverse_port and script_sender_port.

This was implemented by @khssnv Thanks!