Sahara plugins support

Added cluster creation support for the following plugins:
* Vanilla 2.4.1
* HDP 1.3.2 and 2.0.6

Change-Id: Ifbbf973b3666a795663675169da5957709dce8de
Change default endpoint_type to "public"

Change-Id: Ic8935d3069225d95ef800e98c1d9c842f17b4639
Merge "Change default endpoint_type to "public""
Reorganize test module structure

Moved test modules:
 tests/             ->  tests/unit
 test_ci/           ->  tests/ci
 tests_functional   ->  tests/functional
 rally/hacking      ->  tests/hacking

Add testing read me file

Co-Authored-By: Boris Pavlovic <boris@pavlovic.me>
Co-Authored-By: Andrey Kurilin <akurilin@mirantis.com>

Change-Id: I57c09d892da4adf863c358a4d63e3543b50d10b7
Updated from global requirements

Change-Id: Ib6f25a7e39c94b1964541e9792306e272ab74c94
add bash completion script

This patch add a script rally.bash_completion which enables
auto-completion of rally CLI in bash environmnet when running:

python setup.py install
or
python setup.py develop

test:
rally [tab]
rally ta[tab]
rally task [tab]
rally task de[tab]

to-do:
adding a cache to bash-completion result could speed up auto-completion

Change-Id: Ia4c68ccf3faea73da87a93ce64b36545d9d8411c
Fix AttributeError in admin_cleanup

There will be an AttributeError in admin_cleanup when the user has no
tenant attached.

Change-Id: I1e34378dea3fbdf51c4218134d986bb8abf29d02
Closes-bug: 1363888
Merge "add bash completion script"
Remove extraneous vim editor configuration comments

Change-Id: Ie384c5468f805b836cbf2c35fed2fe81845ddc33
Partial-Bug: #1229324
Add detailed description for rally commands

Commands affected:
  deployment, task, use, verify, info, show

This descrition available by -h flag.

Change-Id: I2e0518a3189b4bb6c04187a346dfb5c846c293dc