Changed prefix parameter in Yard .__init__ to lanename
Convention is to use the lanename for the prefix.  so its less confusing to call
it lanename instead of prefix.
renamed clearAllRoadSafe to clearAllKeepSafe
Minor change to acceptance logic for raet version
Merge remote-tracking branch 'upstream/develop' into sam_raet_38
Merge pull request #12344 from SmithSamuelM/sam_raet_38

Minor cleanup