Added downloads/week badge

Added total downloads badge

#553

Python 3.8 is released, so I believe that
it would be nice to declare support for it.

Python 3.8.0 release announcement:
https://discuss.python.org/t/python-3-8-0-is-now-available/2478

* Added time support for --until and --since

* Add urls & hashtags normilazer

Add url in the store model
Add hastash analyser  that change all hastash to lowercase

* Remove WARNING:fake_useragent

Remove fake_useragent warning
WARNING:fake_useragent:Error occurred during loading data. Trying to use cache server https://fake-useragent.herokuapp.com/browsers/0.1.11

* Added timedelta function

* Update version

* Update setup.py

* Update README

These changes add conditions for the deploy.
https://docs.travis-ci.com/user/deployment#examples-of-conditional-deployment

I believe it would be nice to see support for
modern and upcoming versions of Python.