Writes yaml files to a new directory EDXAPP_CFG_DIR

Writes out yaml files in addition to the json files
to a new directory in the (by default) /edx/etc/edxapp
directory
moving cfg dir creation to deploy.yml
Merge pull request #1725 from edx/jarv/config-refactor-wip

Writes yaml files to a new directory EDXAPP_CFG_DIR