DOC updates [skip ci]

updated README.md
update CONTRIBUTING.md
add docs/getting_started_on_windows.md
[skip ci]
It must have been unintentionally missed in the docs. Please add.

Sent from my iPhone

> On Jun 28, 2014, at 1:04 PM, "Rigel St. Pierre" <notifications@github.com> wrote:
> 
> In CONTRIBUTING.md:
> 
> >  
> >  4. **Fire it up! Fire it up! Fire it up!**
> >  
> > -    Now that you've got VirtualBox and Vagrant installed with the source code
> > -    cloned in `~/assemblymade/coderwall` we can start up the Vagrant instance.
> > +    Now that you've got VirtualBox and Vagrant installed with the source code cloned in `~/assemblymade/coderwall` we can start up the Vagrant instance.
> >  
> >          cd ~/assemblymade/coderwall
> >          vagrant up
> >  
> While following this I got this error
> 
> There are errors in the configuration of this machine. Please fix
> the following errors and try again:
> 
> Vagrant:
> * Unknown configuration section 'vbguest'.
> The following fixes it, should this be added?
> vagrant plugin install vagrant-vbguest
> 
> —
> Reply to this email directly or view it on GitHub.