Fixed mismatch between repo name and CMake project name

[elandini84]

This issue is just to let everyone know that, from this commit the repo CMake project name will match the name of the repo.

And so, also the folder created in the ../tour-guide-robot/build/share/ after running cmake, will, from now on, be tour-guide-robot.

So, if for any reason you have any reference (in your code, in your system environmental variables or in your Docker files) to the old name (behavior-tour-robot), remember to update them.