'sprint' when pressing SHIFT
change osg::vec3 to osg::vec3f in World::setUniforms()
change GodNavigation to use _center instead of _eye when moving
remove functions that are unneccecary now

movement now happens through relocation of the _center, the _eye just 'follows' it. so for rotation we don't have to rotate AND move the _eye anymore. We just rotate the _center, and the _eye, which 'looks' at the _center, rotates and moves automatically to follow it.
minor changes
add heightAt() to ElemateTerrain (for one tile currently) + camera lookAt debugger
fix debug uniform
let camera and center adjust height relative to height of terrain at the center position
minor change
add pitch rotation when scolling with mousewheel
add smooth rotation to initial rotation when pressing SPACE
Merge remote-tracking branch 'origin/master' into navigation_enhancement
fix slerp rotation to home orientation
fix moving camera below terrain ground when pitching with mousewheel
Merge pull request #15 from lanice/navigation_enhancement

Navigation enhancement