Replace volatile bool with boost::mutex

Volatile bool is not sufficient to prevent poll() and reconfigure() from
executing concurrently. This causes the nodelet to crash when poll()
releases the image on a closed camera.

Here a mutex is introduced to guard the relevant critical sections.
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Added support for configuring ip and port of parent broker

This commit adds support to the nao camera nodelet to get the
ip and port settings from ros parameters. That way the nodelet
can be configured using launchfiles or using command line parameters via ros.
Search for free port for broker

Setting the local port to zero causes the broker to search for a free port.
In nao_robot/nao_apps/nao_tactile.py this technique is used to make the broker
search for a free port. However this does not appear to be a documented
by aldebaran.
Init ros node before getting parameters

Fix a problem where the pip and pport parameters are always set to their
default values when using the parameter server and not command line arguments.
Added support for connecting to local broker

By doing this the nodelet can connect to a local broker allowing
direct function calls and memory access.

Note that the nodelet will prefer the local broker over one
specified on the command line or using ros parameters.
Merge remote-tracking branch 'origin/implement-critical-section-in-nodelet' into wip
Merge remote-tracking branch 'origin/add-rosparam-for-parent-broker' into wip
Merge remote-tracking branch 'origin/search-for-free-port-cpp-naonode' into wip
Merge remote-tracking branch 'origin/init-ros-before-using-getparam' into wip
Merge remote-tracking branch 'origin/add-support-for-local-broker' into wip

Conflicts:
	naoqi_sensors/src/naoqi_camera.cpp