Add WIP cylinder support.
Merge branch 'master' into wip/cylinder
More work in progress.
Implemented (not yet tested) hit calculation for cylinder.
Implement the is_inside() method for Cylinder.
And actually return the value...
Add new keywords for lexer/parser.
Add output operators for Vectors to aid debugging.
Make raytracing cylinders actually work (at least for a simple example, needs some more testing). Still has some debug output left in...
Recompensate for the hit rounding protection, improves the accuracy of the hit point normal calculation.
Fix setting texture on the cylinder end caps correctly.
Compute discriminant when solving 2:nd degree equattion in double precision.
Avoid more precision loss. Remove debug output.
Use std::max/min to simplify code a bit.