Fixed setBlock not using the location version of getLightOpacity()

This is my first attempt at moding forge and writing a pull request so please forgive me if I've made some stupid mistake.

Anyway currently the setBlock (func_150807_a) method in Chunk uses the simple block.getLightOpacity() to decide whether to update lighting, rather than getLightOpacity(world,x,y,z).

This pull request replaces them with the location version and also moves the call for the block being removed so that it occurs before the block is removed.