change import param to existing

Author: sudo87

source/_static/images/create_dns_zone.png

@@ -255,7 +255,7 @@ Using the API:
 
 .. code:: bash
 
-   cmk create dnszone dnsserverid=<dns-server-id> name="example.com" import=false description="Example DNS zone"
+   cmk create dnszone dnsserverid=<dns-server-id> name="example.com" existing=false description="Example DNS zone"
 
 
 **Parameters**
@@ -276,7 +276,7 @@ Using the API:
    * - ``description``
      - No
      - The description of the DNS zone
-   * - ``import``
+   * - ``existing``
      - No
      - If true, imports an existing DNS zone from the external DNS provider into CloudStack; if false, creates a new DNS zone in both CloudStack and the DNS provider. **Default**: ``false``