Optimize headers (part 2) (#6272)

* Optimize headers (part 2)

* less debug.h in headers
* less remoteplayer.h for everybody

* Cleanup (part 2)

* camera.h: mesh.h
* mapgen.h: mapnode.h
* serverenvironment.h: mapblock.h
* nodedef.h: shader.h

src/particles.h

@@ -23,7 +23,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "irrlichttypes_extrabloated.h"
 #include "client/tile.h"
 #include "localplayer.h"
-#include "environment.h"
 #include "tileanimation.h"
 
 struct ClientEvent;