Redturtle-tiles-management

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- Sorting not enabled on mobile while adding new tile, too [nzambello]
- Fix for IE: used width/float instead of grid [nzambello]

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BREAKING CHANGES:

- Handled tile sizing with a new button with styles given in controlpanel [nzambello]


Other changes:

- Fix IE11 compatibility in js.
[cekk]
- Sorting not enabled on mobile [nzambello]
- Removed container margin, it should be styled by themes, if needed [pnicolli]
- Fix z-index of tileEditButtons [fdelia]

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- Fix data-tile urls generation to don't break subrequest rendering when there
is a reverse proxy configuration with _vh_ (https://github.com/plone/plone.subrequest/issues/17).
[cekk]

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- Fix permission checks in addable tiles vocabulary.
Now use correct permission (name) and not the id.
[cekk]

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- Fix pypi brown bag release
[cekk]

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- Add a loader when tiles are fetched
[cekk]
- Remove empty managers when user can't add tiles
[cekk]
- Refactor manager render view. Now is lighter (no more unused Plone body macros)
and can be used also in static renders
[cekk]