Fix tables display issues

[martinRenou]

We now use adminlte tables which are more responsive

[codecov-io]

Codecov Report

Merging #482 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master     #482   +/-   ##
=======================================
  Coverage   95.33%   95.33%           
=======================================
  Files          88       88           
  Lines        4077     4077           
  Branches      259      259           
=======================================
  Hits         3887     3887           
  Misses        138      138           
  Partials       52       52

Impacted Files	Coverage Δ
...anager/handlers/admin/tests/test_admin_handlers.py	100% <100%> (ø)	⬆️

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[stefanoborini]

Leave the button as it was before and the generalActions as well. We'll find a way of embedding the button in another component at a later stage.

[martinRenou]

As you asked, I left the button as it was before. Excepted that I played with the CSS to display it on top of the datatable instead of on its side. It involves flex-box, but it will be susceptible to be removed when putting the button in the adminlte box header.