Add down command to uninstall and delete data (#1285)

Small improvement to `btrix` helper. Adds `./btrix down` command to
uninstall and delete data without resetting the dev environment.

btrix

@@ -17,11 +17,16 @@
 #   -wait: Wait until pods are ready
 #
 # $ ./btrix reset
-# Uinstall, delete data, then bootstrap
+# Uninstall, delete data, then bootstrap
 # Optional args:
 #   -microk8s: Preface kubectl/helm commands with microk8s
 #   -wait: Wait until pods are ready
 #
+# $ ./btrix down
+# Uninstall and delete data
+# Optional args:
+#   -microk8s: Preface kubectl/helm commands with microk8s
+#
 # $ ./btrix test
 # Run backend tests
 #
@@ -170,4 +175,13 @@ if [[ $1 = "nightly" ]]; then
     runNightlyTests
 fi
 
+# down: stop and uninstall browsertrix cloud
+if [[ $1 = "down" ]]; then
+    if [[ $2 = "$MICROK8S" ]] ; then
+        resetMicrok8s
+    else
+        reset
+    fi
+fi
+
 echo "Done"