Restore offline mode of hardware MTI Ros
Add HardwareSensorCameraRos.

Reads from image topic in Online mode. Compiles but wasn't tested yet.
Refactor FindJafar.cmake

Now we can look for Jafar modules as components passed to a
find_package(). FindJafar.cmake still need to be refactored conform
the guidelines on /usr/share/cmake-<VERSION>/Modules/readme.txt, but
I'm satisfied for now.
Add FindViam.cmake
Refactor compilation of optional modules
Correct sensor mti ros to work on online mode
Add another command to the command list file
Convert image message to MONO8 instead of BGR8.

Not tested. Doesn't know if it will work.
Some changes on Sensor Camera Ros constructors

The constructors were wrong. They were made more like the ones in
HardwareSensorCamera. I can't see the difference between the two
constructors. Looks like one is for online and other for offline
mode. Should compare with HardwareSensorCameraFirewire, but it's not
easy...
Try to use the CameraRos class

Code compiles, but is not tested yet. Should check if the calls are
correct and/or if we need to change the constructors to use it in
online mode correctly.
Refactor CameraRos constructors.

Make only one constructor which initializes the buffer using
HardwareSensorCamera::init().
Remove start method from CameraRos to use the parent one
Push more for a future where we'll have a comprehensive (and simple) main.hpp file

Still not complete though.

Summary:
- Add a node that uses the simplemain.hpp;
- Add demo_slam_simple_stop;
- Put all parameters used into INIT at the beginning of the file

Missing:
- Displays
- Export things

Bug:
- Crashes with segfault when leaving the program. Something with the
  robot destructor and data logger.
Add run and main functions to simplemain.hpp

Compiles but there's a segfault going on into SensorManager.
Add the README file