fix: drop stubs that claim what a phone cannot do (0.1.1)

get_health_metrics, get_ssids, get_radio_info and get_wireless_clients
only raised NotImplementedError. They are left over from when the
driver sat on AccessPointDriver, and a stub makes a capability check
(callable(getattr(driver, name))) answer yes. The application polls
SNMP itself (napalm-device-types docs/STRUCTURE.md); a phone has no
profile to declare.

Also stops tracking the .pyc and egg-info files .gitignore already
lists.

Closes #2

tests/test_capabilities.py

@@ -0,0 +1,14 @@
+"""A method exists on the driver only where the phone can answer it.
+
+The application asks ``callable(getattr(driver, name, None))``; a stub that only
+raises would claim a capability the phone does not have.
+"""
+
+import pytest
+
+from napalm_yealink.yealink import YealinkDriver
+
+
+@pytest.mark.parametrize("name", ["get_health_metrics", "get_ssids", "get_radio_info", "get_wireless_clients"])
+def test_no_stub_claims_what_the_phone_cannot_do(name):
+    assert name not in vars(YealinkDriver)