Tentative Web UI for the Printer device. (#676)

* Tentative Web UI for the Printer device.

* timeout must be a positive value

* Change the attach device class method to accept a dict with arbitrary key value pairs of parameters to be passed to the protobuf interface, rather than hard coded ones. Also renames the RaCtlCmds.attach_image() class method to attach_device().

* Make download_to_iso() use the new attach interface.

* Dynamically get the form items for support devices.

* Change the data structure returned by RaCtlCmds.get_device_types() to a dict, which contains the supported parameters and their default values. Leverage this data in the web ui to derive the form fields from the capabilities of rascsi.

* Tweak UI labels.

* Update FileCmds.read_config() to work with the new RaCtlCmds.attach_device() method.

* Check for numeric value.

* Streamline the UI for support devices.

* Handle support devices better by the oled screen.

* Clean up html.

* Dynamically adjust form field size based on data length.

python/oled/src/rascsi_oled_monitor.py

@@ -188,9 +188,11 @@ def formatted_output():
                 else:
                     output.append(f"{line['id']} {line['device_type'][2:4]} {line['status']}")
             # Special handling of devices that don't use image files
-            elif line["device_type"] in (NETWORK_DEVICE_TYPES + SUPPORT_DEVICE_TYPES):
+            elif line["device_type"] in (NETWORK_DEVICE_TYPES):
                 output.append(f"{line['id']} {line['device_type'][2:4]} {line['vendor']} "
                               f"{line['product']}")
+            elif line["device_type"] in (SUPPORT_DEVICE_TYPES):
+                output.append(f"{line['id']} {line['device_type'][2:4]} {line['product']}")
             # Print only the Vendor/Product info if it's not generic RaSCSI
             elif line["vendor"] not in "RaSCSI":
                 output.append(f"{line['id']} {line['device_type'][2:4]} {line['file']} "