Enable running unit tests without installing.

Now with pytest we no longer need ACTS to be installed to run unit
tests! This means we could easily run unit tests on both py2 and
py3 without dealing with local package nightmares! :D

Remove the integration test from unit test suite.

Add tests/ to distribution package.

Update README to reflect this improvement.

Bug=27701876
Bug=27404910

Change-Id: I76590e623c965256c2bdf5b81197ea0532973581
diff --git a/acts/framework/README b/acts/framework/README
index 1c5faaf..20cf2de 100644
--- a/acts/framework/README
+++ b/acts/framework/README
@@ -10,10 +10,13 @@
   - future
   - pyserial
 
+To run unit tests:
+$ python3 setup.py test
+$ python setup.py test
 
 Setup:
   1. Install the system dependencies.
      On Ubuntu, sudo apt-get install python3.4 python3-setuptools
   2. Run "python3.4 setup.py install" with elevated permissions
   3. To verify ACTS is ready to go, at the location for README, and run:
-     cd tests/ && ./test_acts
+     cd tests/ && act.py -c acts_sanity_test_config.json -tc IntegrationTest