Merge pull request #2 from txthinking/master

up to date
add -d to remove mappings
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
add content.googleapis.com
readme
add gerrit.googlesource.com for android develop

the 'repo' tool google provided will use it to initialize the android build directory
fixed #8
add 0.client-channel.google.com
fixed #9
add use and select