Dynamic reconfigure fix

I've work around the dynamic_reconfigure functionality implemented in rosaria, that I think it wasn't working well.
I've added defaults, minimums and maximums (if known) to the cfg file. If default value is 0 the parameter is set from robot defaults or from parameter server if said parameter is set.

Now rqt_reconfigure starts with the current parameters.

Also, I've added [trans|rot]_vel_max parameters.

The code compiles and I've tested it on my robot. Feel free to verify it before merging it.