Added comment header and copyright.
Added an author list.
Added contributing instructions.
Added instructions to delete the deployment.
Add 'from gce import *' into all tests at top-level.
Updates for Google Python API 1.2 -> 1.3 upgrade.

The change is: `apiclient` -> `googleapiclient`.
Clarify browser config requirement for proxy.

Previously, the need to configure a browser for use with the proxy was buried in
the bullet for starting up the proxy and thus is easiy to gloss over when you
can just copy-paste the URL and get started.

Thus, users would get error messages about inability to resolve the URL because
they did not update their browser's proxy settings with no indication of what to
do to fix the error.
Flesh out the documentation to be stand-alone.

We now have the complete instructions in this README without any references to
the previous version so that we can easily switch over to this model of
deployment.
Move the Jsonnet configs for Ambari to new folder.
Point users to Ambari's new home.
Remove the original CentOS 6 deployment.

We now have a more modular and multi-OS/deployment compatible version in a new
directory, ../ambari, that folks should be using and migrating to.
Point users to the new Ambari dir from parent dir.
Link to the app dir rather than README.md itself.

By sending users to the directory, they will still see the README contents
automatically, but will also have a file browser at their disposal.

By linking directly to the README itself, we were previously just showing the
users the text but without the very useful file browser as well, which can be
used to explore the directory structure, config scripts, etc.
Cleanups: remove old steps; bullets -> numbers.
Fixed spelling.
Added usage to document the flags and options.
Added command to get help on socks script flags.
Highlight username and password.
Fix the command to delete the cluster.
Use `$(COMMON)` to refer to common dir.