Host Enrollment via OTP

The support for host enrollment via one-time-password has been added.
When submitted, the OTP will be used to set the host's userpassword.

Previously each IPA command can only have one JSON test data file.
The ipa_cmd() has been modifies to accept an optional command name.
When used with static files, it will pull the test data whose name
is the same as the command name.

The batch.json has been renamed to ipa_init.json for UI initialization.
Some test data have been added for operations against specific hosts.

install/static/test/data/host_disable_dev.example.com.json

@@ -0,0 +1,9 @@
+{
+    "error": null,
+    "id": 0,
+    "result": {
+        "result": true,
+        "summary": "Removed kerberos key from \"dev.example.com\"",
+        "value": "dev.example.com"
+    }
+}