Prepare for incoming gazebo-yarp-plugins 5 release

[PeterBowman]

Implicit network wrappers (i.e. controlboardwrapper2) will be dropped in favor of a yarprobotinterface plugin:

• gazebo-yarp-plugins 5 release plan robotology/gazebo-yarp-plugins#594
• Migrate camera, multicamera, laser and depthcamera example models to use gazebo_yarp_robotinterface plugin robotology/gazebo-yarp-plugins#615
• Migrate controlboard example models to use gazebo_yarp_robotinterface_plugin robotology/gazebo-yarp-plugins#616
• Discussion: remove implicitly created Network Wrapper Servers (NWSs) by gazebo-yarp-plugins in the future  robotology/gazebo-yarp-plugins#569
• Provide a way for plugins to explicitly disable implicitly created network wrappers server robotology/gazebo-yarp-plugins#585

The new explicit NWS/NWC thing depends on a transitional CMake variable GAZEBO_YARP_PLUGINS_DISABLE_IMPLICIT_NETWORK_WRAPPERS being set to ON (currently defaults to OFF). During said transition, in order to avoid tweaking this while building gazebo-yarp-plugins, it is possible to pass the dynamic disableImplicitNetworkWrapper option through .ini configuration to achieve the same behavior (and make it possible to have two models coexisting: using the new and the old schemes).

Incidentally, this task will also make our models compatible with YARP 3.7, which has officially hard-deprecated the controlboardwrapper2 device.

[PeterBowman]

The disableImplicitNetworkWrapper is a temporary config option that will disappear in the future. There is another similar quirk to be considered: robotology/yarp#2819 has introduced support for the portprefix attribute/parameter in yarprobotinterface at YARP 3.7.

Old code (will be covered in this issue):

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE robot PUBLIC "-//YARP//DTD yarprobotinterface 3.0//EN" "http://www.yarp.it/DTD/yarprobotinterfaceV3.0.dtd">

<robot name="teo_head_nws" portprefix="/teoSim" build="0" xmlns:xi="http://www.w3.org/2001/XInclude">
    <devices>
        <device name="head_nws_yarp" type="controlBoard_nws_yarp">
            <param name="name">/teoSim/head</param>
            <param name="period">0.01</param>
            <action phase="startup" level="5" type="attach">
                <param name="device">controlboard_plugin_device</param>
            </action>
            <action phase="shutdown" level="5" type="detach" />
        </device>
    </devices>
</robot>

New code (to be applied after YARP 3.7 is well-established):

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE robot PUBLIC "-//YARP//DTD yarprobotinterface 3.0//EN" "http://www.yarp.it/DTD/yarprobotinterfaceV3.0.dtd">

<robot name="teo_head_nws" portprefix="/teoSim" build="0" xmlns:xi="http://www.w3.org/2001/XInclude">
    <devices>
        <device name="head_nws_yarp" type="controlBoard_nws_yarp">
            <param name="name">/${portprefix}/head</param>
            <param name="period">0.01</param>
            <action phase="startup" level="5" type="attach">
                <param name="device">controlboard_plugin_device</param>
            </action>
            <action phase="shutdown" level="5" type="detach" />
        </device>
    </devices>
</robot>

Edit: portprefix done at 7a7f0c2.

[PeterBowman]

cc @roboticslab-uc3m/teo: please update https://github.com/robotology/gazebo-yarp-plugins to v4.2+ in order to keep using our models (note this requires Gazebo 11).