Convert backslashes to forward slashes in include paths
Lots of changes for standards compliance and debian buildability

 * Add const-correctness to many classes
 * Adjust CMakeLists to assume you have a reasonable environment
 * * This might not be valid on non-unix-like. Please review
 * Type agnostic and interoperable vector3d class
Merge branch 'debian' into develop

Conflicts:
	include/data/voxel_array.h
	include/data/voxel_data.h
	include/services/event_service_events.h
Merge latest development from Eldalar