Add hello_world.rb
Modify hello_world.rb
Add user related classes
Add new method say_hello_to
Change say_hello_to to say_hi_to
Refactor say_hello_to to greet
Merge branch 'ej_branch'

Conflicts:
	hello_world.rb
Merge branch 'master' of github.com:ejaypcanaria/intro_to_git