Update README.md

add centos
Rename install-font.sh to install-font-ubuntu.sh

rename
Create install-font-centos.sh

add support for centos
Update install-font-centos.sh
Update install-font-ubuntu.sh
Update README.md
Update README.md
Update install-font-centos.sh
Update install-font-ubuntu.sh
Merge pull request #3 from pengjingwen1994/master

Hi, I added centos support for this git