Toggle off all comments

[SamuelCabralCruz]

Would be nice to have a flag to toggle off all generated comments not only the package one.

[SamuelCabralCruz]

For the time being, I made a simple make recipe with the following snippet after the execution of mockgen:

	@head -n 2 $(destination) > $(destination).tmp
	@grep -v '^//' $(destination) >> $(destination).tmp
	@mv $(destination).tmp $(destination)

where destination is the location of the auto-generated file