note where fonts came from.

README.md

@@ -46,7 +46,7 @@ cp -v dist/mermaid.js* ../mkdocs-docs/docs/js/
 cd ../
 python --version
 pip --version
-sudo apt-get install pip
+sudo apt-get install python-pip
 
 wget https://bootstrap.pypa.io/get-pip.py
 sudo python get-pip.py