message: Added a more descriptive slack button!
  feat(doc): add a more descriptive slack button!
diff: @@ -13,7 +13,7 @@ Best way to quickly integrate <a href="https://getbootstrap.com/">Bootstrap 3</a
  <a target="_blank" href="https://opencollective.com/ngx-bootstrap"><img src="https://opencollective.com/ngx-bootstrap/tiers/backer/badge.svg?label=backer&color=brightgreen" />
  <br/>
  -<a href="https://join.slack.com/t/ngx-home/shared_invite/enQtNTExMTY5MzcwMTM0LWVjZGU2MjI4MTVhMGVlMTc2OWRiMzA0NzBhNDU5YzQ0MDM3MWI5NzJjZTUzNzIxZmNjYmFlMjU2MzE0YmY0NWY"><img src="https://a.slack-edge.com/66f9/img/icons/ios-256.png" width="25" height="25" alt="slack" ></a>
  +<a href="https://join.slack.com/t/ngx-home/shared_invite/enQtNTExMTY5MzcwMTM0LWVjZGU2MjI4MTVhMGVlMTc2OWRiMzA0NzBhNDU5YzQ0MDM3MWI5NzJjZTUzNzIxZmNjYmFlMjU2MzE0YmY0NWY"><img src="https://thehomeofthefuture.files.wordpress.com/2018/12/Joinslack.png" width="20%" alt="slack" ></a>
  </p>
  ## Links
  