ref(Makefile): refactor `make dev-release`

This allows us to run `make -C controller config` when we know that
the image is pushed onto the registry and we just need to tell the
cluster to use this image.
fix(registry): make deis-cache mandatory

Sometimes the redis cache would take longer than the registry to come
up. In that case, confd would then set the host and port to be "",
in which case the registry would parse the YAML value as `None`. This
change makes the cache mandatory in order for the registry to come up.
fix(registry): use YAML's nil type
docs(managing_deis): update controller_settings.

Controller has itself as a dependency. Remove it.
Merge pull request #2096 from chuenlye/docs-update-controller-settings

docs(managing_deis): update controller_settings.
support for multiple make discovery-url runs
ref(logger): just use go. remove bash script.
fix(logger): the test is expecting the message "deis-logger running".
Merge pull request #2098 from cleblanc87/master

fix(Makefile): fix multiple make discovery-url runs
ref(logger): replace deis/go.
ref(project): replace deis/go with golang:1.3.
Merge pull request #2117 from aledbf/replace_deis_go_with_golang

ref(project): replace deis/go with golang:1.3.
Merge pull request #2113 from aledbf/logger_to_just_go_refactoring

ref(logger): just use go. remove bash script.
Merge pull request #2090 from bacongobbler/mandatory_cache

fix(registry): make deis-cache mandatory
Merge pull request #2047 from bacongobbler/push-config

ref(Makefile): refactor `make dev-release`