Started some overview documentation of the HaaS.

For a very generous definition of "started." The intent is for this to
become something a new developer can read to get up to speed quickly.
README: linked to overview.
More work on overview docs
Fancy ascii art diagram

Will write some prose to go with this soon.

Also hard-wrapped some of the text; this makes things easier in offline
text editors.
Fixed a typo.
Wrote about how the network is set up by the HaaS
Merge branch 'devel' into overview-docs
Wrote a primer on vlans

This resolves issue #49.
Wrote a bit about of managed vs. unmanaged switches.

Ritesh suggested that this would be useful.
Added some documentation about drivers.

Specificaly, the drivers package now has documentation about the standard
interface that a driver must implement. As noted, the error handling behavior
needs to be decided on and documented.
Reworded documentation to avoid implementation details.

The bit about no-ops isn't something the user should care about - the
functions just shouldn't be used at all.
Merge pull request #63 from zenhack/devel

Wrote an actual description for the README.
Merge pull request #59 from CCI-MOC/driver-docs

Driver docs
Merge pull request #50 from CCI-MOC/vlan-primer

Wrote a primer on vlans
Merge branch 'devel' into overview-docs

Conflicts:
	README.md
Merge pull request #37 from CCI-MOC/overview-docs

Overview docs