I Installed Server.app on Yosemite to enable caching, but see many server processes in Task Manager (_xcsbuild and _devicemgr and _calendar processes)
Solution 1:
You can stop the _xcsbuild "session" by running sudo xcrun xcscontrol --shutdown. This will also stop it from starting at launch.
Although it's probably a better idea to use xcscontrol, the individual launchctl tasks are:
com.apple.xcsd.plistcom.apple.xcscouch.plistcom.apple.xcsredis.plistcom.apple.xcscontrol.plist
You can also delete all the remaining data by running sudo xcrun xcscontrol --reset.
I'm still looking myself for _devicemgr and _calendar, but just this one is enough to let you shut down/reboot without the warning.