Optimize: create Uint32Array() only once
Add note about probably not needed try/catch for getRandomValues()
Simplify: use +string instead of Number(string)
Add link to GitHub
Update demo link: .github.com -> .github.io
Use msCrypto.getRandomValues(), if available
(IE 11+)
http://msdn.microsoft.com/en-us/library/ie/dn280995%28v=vs.85%29.aspx
Add note about used random generator