Remove hosts from /etc/hosts on suspend
Added external ip sample
Rework wording for external IP address example

See #395
Merge branch 'pr/395'

Fixes #395
Merge pull request #491 from miya0001/remove-hosts-on-suspend

Remove hosts from /etc/hosts on suspend
switching to apt-key so that we can use port 80 to get around a restrictive proxy
see this post: http://superuser.com/questions/64922/how-to-work-around-blocked-outbound-hkp-port-for-apt-keys
Removed commented out lines
Retrieve the signing key for Nginx from nginx.org

The key we were using is way outdated from when we actually used
the Ubunto repositories for nginx. We can grab the signing key
from Nginx on the fly and apply it before installing.
Provide output beyond generated "OK" for nginx signing key
Clean up processing of nodejs signing key
Merge pull request #495 from Varying-Vagrant-Vagrants/pr/446

[PR] Clean up GPG signing key handling

Fixes #446
Fix the ability to generate call graph images with Webgrind and graphviz.

Webgrind's default config sets the path for graphviz to /usr/local/bin/dot, and during provisioning, apt-get installs graphviz to /usr/bin/dot. So the proposal here is to simply symlink /usr/local/bin/dot to /usr/bin/dot -- without which you can't currently generate call graphs in Webgrind.
Update docs around Graphviz symlink
Merge branch 'pr/463'

Fixes #463
Un-neglect recent contributors and add to the README
Merge pull request #496 from Varying-Vagrant-Vagrants/un-neglect-contributors

Un-neglect recent contributors and add to the README
Use HTTP for network detection rather than ping

Relying on ping to detect network connectivity was troublesome as
some networks block icmp and would generate a false error. As we
need HTTP access throughout provisioning anyway, we can rely on
it as an indicator of network health.

This ends up being quite a bit faster too. We could probably get
even better with just a DNS request, but that may hide another
issue depending on the network.

Fixes #428
Merge pull request #497 from Varying-Vagrant-Vagrants/network-detection

[PR] Use HTTP for network detection rather than ping
Improve the Ruby code in Vagrantfile, especially fetching the hosts to pass to the hostsupdater plugin
Improve readability of condensed code in Vagrantfile