restore sources.txt
generalize ManagedResource
use system-filepath
less bytestring
use cabal-constraints
remove unneeded Cereal instances
Implement basic scheduling functionality.
Refactor agentHandlers.

* DPP.ManagedProcess API handlers are now included in the
agent handler functions, which simplifies the function signature
from a client point of view.

* Eliminated most of the duplicate code in the agent handlers.

* Updated Servers to use the new handlers.

* Logging of request is currently broken and TODO pending a logging
overhaul.
Miscellaneous package changes:

* Update package cabal fields.

* Update readme to better explain the current project vision.

* Move texpect to TestHelpers and expand use of it where appropriate.

* Use cabal freeze (pre-release) rather than cabal-constraints