Fixed an issue causing slicing not to work due to a change in how the used sarge library works
Fixed an issue causing slicing not to work due to a change in how the used sarge library works

Starting commands asynchronously now necessitates a call to Pipeline.wait_events in order to be able to access the started Command instances. Not waiting causes the list of commands to be not fully populated and hence issues with code depending on that stuff being present.

Conflicts:
	src/octoprint/plugins/cura/__init__.py

mrbeam/OctoPrint,mrbeam/OctoPrint,mrbeam/OctoPrint