2.2 beautify README.md
2.2 beautify README.md

Changes:
- introducing the framework at the beginning
- add a few links for better understanding
- markdown the installation instructions

LuckyCyborg/framework,simple-mvc-framework/framework,LuckyCyborg/simple-mvc-framework,nova-framework/framework,danvers/enrollment-tool,XTRO123/framework,LuckyCyborg/simple-mvc-framework,LuckyCyborg/simple-mvc-framework,geomorillo/framework,geomorillo/framework,geomorillo/framework,LuckyCyborg/framework,danvers/enrollment-tool,XTRO123/framework,simple-mvc-framework/framework,danvers/enrollment-tool,XTRO123/framework,LuckyCyborg/simple-mvc-framework,nova-framework/framework