Support for Cameras with high Opening Angles

[maltewi]

Currently Mars seems not to support cameras with high opening angles (>pi) . It should be investigated why this is the case and if there's a possibility to support them.

Here's what written on the terminal when including a camera with high opening angle:

mars_app: /build/rock-master-18.01-simulation-mars-graphics-0.20171213/src/GraphicsCamera.cpp:371: virtual void mars::graphics::GraphicsCamera::setFrustumFromRad(double, double, double, double): Assertion `(horizontalOpeningAngle < M_PI) && (horizontalOpeningAngle > 0)' failed.

I think we exit with an error! Signal: 6

[malter]

I don't see a reason for that limitation. You can comment the assert calls or build as release to ignore them. The camera should be rendered correctly. If you can confirm this, I will remove the restriction with the next update of the master branch.