Add Qtech model and template; clean up Mikrotik model

- Introduced a new `Qtech` model with a corresponding TTP template for parsing QTECH devices.
- Removed commented-out methods in the `Mikrotik` model to improve code clarity and maintainability.

oxi/interfaces/models/qtech.py

@@ -0,0 +1,7 @@
+from oxi.interfaces import register_parser
+from oxi.interfaces.base import BaseDevice
+
+
+@register_parser(["QTECH"])
+class Qtech(BaseDevice):
+    template = "qtech.ttp"