Remove useless requirements
Remove useless requirements

1. What is the problem
cliff,WebTest and pylint modules present in test-requirement.txt file are
not used anymore.

2. What is the solution to the problem
Remove cliff,WebTest and pylint modules from
test-requirement.txt not used anymore.

3. What the features need to be implemented to the Tricircle
   to realize the solution
None

Change-Id: I6511571a62e341d41dc1069b1af50e27c5bdd14a

openstack/tricircle,stackforge/tricircle,openstack/tricircle,stackforge/tricircle