Create lgtm config (#4213)

* Create lgtm config

* remove exclusions

.lgtm.yml

@@ -0,0 +1,9 @@
+# docs: https://lgtm.com/help/lgtm/lgtm.yml-configuration-file
+
+path_classifiers:
+  test:
+    - exclude: python.d/python_modules/third_party/*
+    - exclude: python.d/python_modules/urllib3/*
+    - exclude: python.d/python_modules/pyyaml2/*
+    - exclude: python.d/python_modules/pyyaml3/*
+