add doc for /xpub/import/status endpoint

doc/GET_xpub_import_status.md

@@ -0,0 +1,37 @@
+# Get import status for a HD Account
+
+Check if an import or a rescan is currently processed by Dojo for a given HD Account.
+
+```
+GET /xpub/:xpub/import/status
+```
+
+## Parameters
+* **:xpub** - `string` - The extended public key for the HD Account
+* **at** - `string` (optional) - Access Token (json web token). Required if authentication is activated. Alternatively, the access token can be passed through the `Authorization` HTTP header (with the `Bearer` scheme).
+
+### Example
+
+```
+GET /xpub/xpub0123456789/import/status
+```
+
+#### Success
+Status code 200 with JSON response:
+```json
+{
+  "status": "ok",
+  "data": {
+    "import_in_progress": false
+  }
+}
+```
+
+#### Failure
+Status code 400 with JSON response:
+```json
+{
+  "status": "error",
+  "error": "<error message>"
+}
+```