Enable Xdebug autostart by default

It's usually annoying to remember that a specific GET or POST parameter is required when initiating a remote Xdebug session. Because we have Xdebug turned off by default, it doesn't seem to hurt to have autostart enabled when Xdebug is turned on.
Always enhancing the README...

May need to go back in and add some links to Wiki articles. I'm on a plane.

Still working on the best way to describe how to use VVV, but I think this comes a lot closer.
Bump version number of WordPress in the README

Since `provision.sh` [links to latest.tar.gz](https://github.com/10up/varying-vagrant-vagrants/blob/master/provision/provision.sh#L295), it's now automatically pulling in 3.5.2 -- README is out of date.
fixed some spacing issues that have been bugging me for months
Merge pull request #87 from carldanley/master

Fix some spacing issues
Merge pull request #86 from kadamwhite/upgrade-wp-version-number

Bump version number of WordPress in the README
Capture a ping_result to determine network status

Capture a basic ping result to one of Google's DNS servers to try and determine if outside access is available to us. If it isn't, we'll want to skip a few things in the future rather than creating a bunch of errors.
Wrap major update/installation procedures in network check

If we don't have a network available to us, we should skip some of the updating and installing that happens throughout the provisioning script.

In a future commit, we'll want to provide some additional information about the boot process, including this network status.
Get with the syntax, yo.
2 pings is enough to determine network availability.

I'll trade a bit of accuracy for a bit of speed in this case. If you need 3 pings to establish network connectivity, then your network needs a hug.
Provide some messaging to indicate network status after provisioning
Hmm. s/externa;/external/ apparently.
Silence package checks when not installed.

dpkg throws a big red error for packages when we find them to not be installed. It's nicer for us to not pollute the screen whenever this happens.
Inline docs refresh for provisioning
Update Virtualbox download note to 4.2.16, add guinea pig warning.

4.2.14 broke Vagrant in a very annoying way, forcing anyone that had upgrade or installed the latest to roll back to 4.2.12. Thankfully, 4.2.16 was just released and resolves this issue.

Added a referencing the older downloads page just in case a new release comes out and somebody finds these instructions before we have properly tested things.

Closes #90
Agent Forwarding
Updated contributors list.
Updated inline documentation in Vagrantfile
Remove poor attempt at Bootstrapifying the dashboard.

This was poor judgement. We should have a vision for the dashboard screen before we start assinging styles to it. I think this was me being lazy.

I'm pulling this out in advance of the 0.8 release. We should have a dashboard discussion in an issue.
Silence network check output

Do a better job of checking the string from our ping check so that it doesn't spew junk all over the provisioning screen. Much more pleasant.