Auto merge of #509 - saneyuki:home, r=saneyuki
Auto merge of #509 - saneyuki:home, r=saneyuki

server: Use os.homedir().

This api is introduced since iojs v2.3.0
https://github.com/nodejs/node/blob/v2.3.0/CHANGELOG.md

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karen-irc/karen,karen-irc/karen