Cycles:

* Fix missing update when editing objects with emission materials.
* Fix preview pass rendering set to 1 not showing full resolution.
* Fix CUDA runtime compiling failing due to missing cache directory.
* Use settings from first render layer for visibility and material override.

And a bunch of incomplete and still disabled code mostly related to closure
sampling.

intern/cycles/render/tile.cpp

@@ -96,7 +96,7 @@ void TileManager::set_tiles()
 
 bool TileManager::done()
 {
-	return (state.pass+1 >= passes);
+	return (state.pass+1 >= passes && state.resolution == 1);
 }
 
 bool TileManager::next()