removed unused import
modified GCE test to specify a persistent disk
cleaning up gce tests
extracted duplicated uaserver mocks to a method
extracted duplicated appcontroller mocks to a method
extracted ec2 duplicate code to helper method
extracted checks for appscale compatibility to helper method
extracted common socket mocks to helper method
added new --disks flag, to let users specify EBS or PD disks in EC2/Euca/GCE
warning users who try to start appscale in a cloud environment without specifying EBS/PD mounts to back up their data
refactored node_layout to be more concise
style cleanup on node layout tests
style cleanup on ec2 agent
validating that users pass in one EBS/PD disk per machine in EC2/GCE
validating that PDs exist in GCE before using them
passing persistent disk info to AppController
passing over locations as a json dict instead of a colon-delimited string
unmounting, then detaching any persistent disks we added on cloud creation
specifying zone when validating persistent disks
correctly passing in --disks flag to run-instances