Update to awsbox 0.4.5
Add awsboxen profile to build a custom mysql storage node.
Add awsboxen profile to build a custom cassandra storage node.
Update loadtest suite to use awsboxen deployment profiles.
Update to awsboxen 0.1.1, and use it for the loadtests
Merge pull request #78 from mozilla/custom-backend-loadtests

Custom backend loadtests
Update to awsboxen v0.2.0; but version reqs in profile config
Refuse to run loadtests if an old version of awsboxen is installed.