Extract global actions from datatable

[martinRenou]

The datatable component should only take care of rendering the datatable. As buttons for global actions are not part of the datatable itself, I think it's better to render them from the components which render the datatable.
Furthermore, it allows us to render those buttons inside the box-tools element provided by AdminLTE, which is the proper place for those buttons, it improves the visual aspect.

[codecov-io]

Codecov Report

Merging #540 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #540   +/-   ##
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  Coverage   95.18%   95.18%           
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  Files          85       85           
  Lines        3905     3905           
  Branches      247      247           
=======================================
  Hits         3717     3717           
  Misses        137      137           
  Partials       51       51

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