Cleanup Makefile and test suites in preparation for new CD pipeline

As part of the preparation for updater, this PR cleans up the `Makefile` and prepares our test suites for a new CI/CD pipeline.

### Makefile changes

 * Fix `dev-registry` target to handle stopped registries
 * Fix error handling bug with `foreach` loops in the root `Makefile`
 * Add new `dev-release` target which cuts a release from the current source tree
 * Add new `deploy` target that calls `build dev-release restart` for easy hacking
 * Rename `DEIS_REGISTRY` to `DEV_REGISTRY` for clarity
 * Add `make build` target to client so we can use `client/dist/deis` binary in the test suites
 * Build clients (deis & deisctl) as part of `make build`

### Test suite changes

 * Factored out common test setup logic into `tests/bin/test-setup.sh`
 * Refactored existing tests like `test-integration.sh` to use common setup logic
 * Modified `test-nightly.sh` to test with public artifacts (not the local source tree)
 * Added `cleanup` and `dump_logs` callbacks to all tests
 * Switched tests from 1-node to 3-node Vagrant
 * Added prints and timing information throughout suites to provide better log feedback

This PR also includes a work-in-progress `test-acceptance.sh` script designed to test the updater.