add class comment for dao
Merge commit 'e9cfab5111347eb7290de038b2e6284ea7a845ba' into dev
Merge pull request #3 from cnnic/dev

Dev
refine dao comment
add iputil test
Merge remote-tracking branch 'origin/dev' into dev
Merge pull request #4 from cnnic/dev

Dev
Merge pull request #345 from wade1012/dev

Dev Wade