Missing header includes

This bug is for player 2.1.1.

When building under fedora, there are functions referenced in the source that are not included with preprocessor commands. As such, the compiler doesn't recognize them and the build process aborts.

The files/modules are:

In server/drivers/laser/lms400_cola.cc:
#include <unistd.h>

In server/drivers/mixed/mricp/src/map.cpp:
#include <stdlib.h>

In server/drivers/mixed/mricp/src/geometry2D.cpp:
#include <stdio.h>

I did not make a patch since these are relatively easy to fix.