Adding a "health check" for the sinatra test app

* This will help identify failures caused by runtime issues
Adjusting max_storage_mb for bosh-lite

Reduce max_storage_mb sizes of each plan when deploying to bosh lite and running
acceptance tests manually
Bump src/cf-mysql-broker

Bump cloudfoundry/cf-mysql-broker:
  Alex Stupakov:
     Remove max_db_per_node limit for instance creation ( Travis Success: https://travis-ci.org/cloudfoundry/cf-mysql-broker/builds/27994145 )