Remove rejoin-stack.sh

This command has never completely worked to restart DevStack.
It periodically prompts attempts to work around this brokenness
in ways that harm other functions.  Let's finally remove it.

Requiring a complete re-run of DevStack after a reboot has always
been intentional.

TODO: follow-up cleaning all of the screen hackage if this merges.

Change-Id: I2f61bb69cc110468a91dcaa4ee7653ede7048467

Author: Dean Troyer

functions-common

@@ -1643,7 +1643,7 @@ function service_check {
     done
 
     if [ -n "$failures" ]; then
-        die $LINENO "More details about the above errors can be found with screen, with ./rejoin-stack.sh"
+        die $LINENO "More details about the above errors can be found with screen"
     fi
 }