Implement testing for activities. Fixes T867

Summary:
 - Replace espresso with spoon.
 - Update readme on how to run tests with the spoon testing framework.
 - Add test cases for `DeploymentActivity`.
 - Add test cases for `AddDeploymentActivity`.
 - Implement a workaround for a bug in `dexmaker` causing test to throw an exception when
   test is run on v4.3 and above.
 - Refactor how `AddDeploymentFragment` is added to tablet devices. Determine if there is a
   container for adding the `AddDeploymentFragment` fragment.

Test Plan: - Run `./gradlew spoon`

Reviewers: dkobia, PapaLee

Subscribers: rjmackay, shadowhand

Maniphest Tasks: T867

Differential Revision: https://phabricator.ushahidi.com/D430