Remove testrepository

This commit is a follow-up of "switch to using stestr"
which was merged already [1].
After switch to using stestr, testrepository is unnecessary
and should be removed.

[1] https://review.openstack.org/571975

Change-Id: I702720f5fcebbd9b0fa0e7e387c7a4d3f1bf4542

.gitignore

@@ -31,8 +31,6 @@ pip-log.txt
 # Unit test / coverage reports
 .coverage
 .tox
-nosetests.xml
-.testrepository
 .venv
 tools/lintstack.head.py
 tools/pylint_exceptions

lower-constraints.txt

@@ -81,7 +81,6 @@ sphinxcontrib-websupport==1.0.1
 stestr==1.0.0
 stevedore==1.20.0
 suds-jurko==0.6
-testrepository==0.0.18
 testscenarios==0.4
 testtools==2.2.0
 traceback2==1.4.0

test-requirements.txt

@@ -9,7 +9,6 @@ reno>=2.5.0 # Apache-2.0
 sphinx!=1.6.6,!=1.6.7,>=1.6.2 # BSD
 openstackdocstheme>=1.18.1 # Apache-2.0
 oslotest>=3.2.0 # Apache-2.0
-testrepository>=0.0.18 # Apache-2.0/BSD
 testscenarios>=0.4 # Apache-2.0/BSD
 testtools>=2.2.0 # MIT
 stestr>=1.0.0 # Apache-2.0