* Remove .testr.conf as there is no tests dir and update .gitignore
accordingly
* Use 3.18.0 as the minversion for tox and replace whitelist_externals
by allowlist_externals and remove unused allowlist_externals
Signed-off-by: HeroicHitesh <email.hiteshkumar@gmail.com>
Change-Id: Iaca746c0ad67fee7972943beab7aca0ee314e2ed