Add test for ceilometer deployment with mongo

Add verification for ceilometer deployment with mongo:
* deploy simple with mongo(mongo on separate node)
* deploy multinode with mongo (mongo with other roles)
* deploy ha (mongo on separate node)
* deploy ha multinode(mongo with controllers)

Change-Id: I60553788a3ce277bf1b9db262b23e71a2969918f
Closes-bug: #1277037
Merge "Add test for ceilometer deployment with mongo"
flake8 fixes for fuelweb_test

Added flake8 check to run_test.sh for CI checks
flake8 check ignores temporary files created when
running fuelweb_test.
Change-Id: I4bf99b63b1c690c0d86f0a20bc86fe9ecd9ccfb2
Closes-Bug: #1261547