Add kcadm wrapper for keycloak

This wrapper automatically handles auth and server via Ansible vault information that we have already.

misc/kcadm_wrapper.sh

+#!/usr/bin/env bash
+#
+# Script that wraps kcadm.sh to securely get our credentials.
+#
+# Example invocation:
+# misc/kcadm_wrapper.sh get realms
+#
+kcadm "$@" --no-config --server https://accounts.archlinux.org/auth --realm master --user $(misc/get_key.py group_vars/all/vault_keycloak.yml vault_keycloak_admin_user) --password $(misc/get_key.py group_vars/all/vault_keycloak.yml vault_keycloak_admin_password)