Remove unused environment data and add a way to persist state between tasks (per-host)
Fixed projects for VS2012
Refactored out XML serialization for Host and created
IHost interface to allow serializable subclasses when necessary.
Renamed IDeployment to IDeploymentTasks to be more
clear on what the interface represents.
Removed superfluous Env class and merged properties
into IDeploymentContext interface
Added OperationsFactories to control creation of local and
remote operations and a way to initialize a host from an SSH host
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