Update Intro.md
Update Intro.md

Some improvement and fixing errors in documentation
vulvulune/validation,hitesh97/validation,Zensavona/validation,Bcpoole/validation,PWKad/validation,jdanyow/validation,vulvulune/validation,RichTeaTime/validation,ericIMT/validation,milunka/validation,mbroadst/validation,ericIMT/validation,manuel-guilbault/aurelia-validation,aurelia/validation,RichTeaTime/validation,JeroenVinke/validation,mbroadst/validation,charlespockert/validation,JeroenVinke/validation,PWKad/validation,aurelia/validation,manuel-guilbault/aurelia-validation,milunka/validation,DaveGee/validation,DaveGee/validation,Bcpoole/validation