Merge pull request #2 from txthinking/master

up to date
Update updateHosts.go
fix for reading hosts file

On my osx, use a+ to open a file couldn't read any content, use r for
generally.
Merge remote-tracking branch 'LYY/master' into develop

fix #3
update script
update .py
Merge pull request #3 from txthinking/master

update
Update updateHosts.go
format
Update updateHosts.go
merge #6
fixed #4