Rename 'Civility Policy' -> 'Code of Conduct'
Refer to the Ruby workshop instead of January
Refer to the workspace directory in example command prompt

Just to make it look a tad closer to what they might see. Might also ensure that
they're in the right directory when they're doing this.
Remove redundant instruction to create workspace folder
Merge pull request #160 from railsbridge-boston/code-of-conduct

Rename 'Civility Policy' -> 'Code of Conduct'
Update VirtualBox and Vagrant minor versions for September workshop

These are the versions that will be used to build the VM. Looks like
only minor updates.
Change the box name so we don't need to vagrant box remove

I am optimizing the box name here for human speech, so it's not exactly
the same as the filename. See #155.