Update nox config to run on both trace and stats(PR pending) (#153)

Author: liyanhui1228

nox.py

@@ -35,7 +35,7 @@ def unit(session, py):
     session.run(
         'py.test',
         '--quiet',
-        '--cov=opencensus.trace',
+        '--cov=opencensus',
         '--cov-append',
         '--cov-config=.coveragerc',
         '--cov-report=',
@@ -83,7 +83,7 @@ def lint(session):
     session.interpreter = 'python3.6'
     session.install('flake8')
     session.install('.')
-    session.run('flake8', 'opencensus/trace')
+    session.run('flake8', 'opencensus/')
 
 
 @nox.session

opencensus/__init__.py

@@ -15,6 +15,6 @@
 try:
     import pkg_resources
     pkg_resources.declare_namespace(__name__)
-except ImportError:
+except ImportError:  # pragma: NO COVER
     import pkgutil
     __path__ = pkgutil.extend_path(__path__, __name__)