Updating coveragerc omit section for namespace collisions.

This includes omitting our __init__ files (since namespace
packages don't actually have __init__ get imported) and
omitting "google.cloud.logging.v2" and "google.cloud.pubsub.v1"
since they are in our "google.cloud" namespace package but
are not owned by us.

Author: dhermes

.coveragerc

@@ -1,6 +1,26 @@
 [report]
 omit =
     */_generated/*.py
+    # Namespace package __init__ files.
+    google/__init__.py
+    google/cloud/__init__.py
+    google/cloud/bigquery/__init__.py
+    google/cloud/bigtable/__init__.py
+    google/cloud/datastore/__init__.py
+    google/cloud/dns/__init__.py
+    google/cloud/error_reporting/__init__.py
+    google/cloud/language/__init__.py
+    google/cloud/logging/__init__.py
+    google/cloud/monitoring/__init__.py
+    google/cloud/pubsub/__init__.py
+    google/cloud/resource_manager/__init__.py
+    google/cloud/storage/__init__.py
+    google/cloud/streaming/__init__.py
+    google/cloud/translate/__init__.py
+    google/cloud/vision/__init__.py
+    # Packages in the "google.cloud" package that we don't own.
+    */google/cloud/logging/v2/*
+    */google/cloud/pubsub/v1/*
 show_missing = True
 exclude_lines =
     # Re-enable the standard pragma