Rename 'draw' or 'drawcall' to action

* There's not a good accepted terminology for this kind of event, and for
  historical reasons 'drawcall' has been the accepted term, even though
  that can be quite confusing when a dispatch or a copy is a 'drawcall'.
* This is particularly highlighted by the event browser filters where
  $draw() includes draws and dispatches, but $dispatch() only includes
  dispatches, it's hard to intuitively understand why $draw() matches all
  of these calls.
* As a result we've defined the term 'action' to cover these types of
  events in the same way that we defined 'event' in the first place to
  mean a single atomic API call.

docs/python_api/examples/renderdoc/decode_mesh.py

@@ -94,7 +94,7 @@ def getMeshInputs(controller, draw):
 		meshInput.numIndices = draw.numIndices
 
 		# If the draw doesn't use an index buffer, don't use it even if bound
-		if not (draw.flags & rd.DrawFlags.Indexed):
+		if not (draw.flags & rd.ActionFlags.Indexed):
 			meshInput.indexResourceId = rd.ResourceId.Null()
 
 		# The total offset is the attribute offset from the base of the vertex
@@ -223,7 +223,7 @@ def printMeshData(controller, meshData):
 def sampleCode(controller):
 	# Find the biggest drawcall in the whole capture
 	draw = None
-	for d in controller.GetDrawcalls():
+	for d in controller.GetRootActions():
 		draw = biggestDraw(draw, d)
 
 	# Move to that draw