Cycles: Separation of Indirect and Direct clamping.

Indirect and Direct samples can now be clamped individually. This way we can clamp the indirect samples (fireflies), while keeping the direct highlights.
Example render: http://www.pasteall.org/pic/show.php?id=66586

WARNING: This breaks backwards compatibility. If you had Clamping enabled in an old file, you must re-enable either Direct/Indirect clamping or both again.

Reviewed by: brecht
Differential Revision: https://developer.blender.org/D303

intern/cycles/render/integrator.h

@@ -50,7 +50,8 @@ public:
 	int seed;
 	int layer_flag;
 
-	float sample_clamp;
+	float sample_clamp_direct;
+	float sample_clamp_indirect;
 	bool motion_blur;
 
 	int aa_samples;