removed LOG_DEVEL messages during cluster start
removed LOG_DEVEL messages during cluster start

Those were only visible in maintainer mode, and were intended to find a
cluster startup problem in Jenkins. However, the problem didn't show up
there again, so the messages will now be retired.

wiltonlazary/arangodb,wiltonlazary/arangodb,arangodb/arangodb,wiltonlazary/arangodb,wiltonlazary/arangodb,arangodb/arangodb,wiltonlazary/arangodb,wiltonlazary/arangodb,arangodb/arangodb,arangodb/arangodb,arangodb/arangodb,wiltonlazary/arangodb,arangodb/arangodb,wiltonlazary/arangodb,arangodb/arangodb,arangodb/arangodb