Bug 1084163 - Remove 'make check' from automation/build; r=glandium

'make check' is somewhat special in that we want to trigger testers
before it finishes. Since moving sendchange into mach is difficult and
'make check' may be going away in the future anyway, just pull it out
for now.

Also remove the MOZ_AUTOMATION_*_SENDCHANGE flags since we aren't using
them.
Bug 1085026 - Use sha512 hashes for mar files; r=glandium