Collective-themefragments

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- Fix to hide fragments with empty title from tile menu
[datakurre]

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- Fix issue where fragments didn't render when traversed from a view context
[datakurre]

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- Fix issue where fragment was not properly decoded
[datakurre]

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- Upgrade Theme fragment tiles with custom scheme to support layout aware
tile data storage introduced in plone.app.blocks 4.0
[datakurre]

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- Refactor fragment tile source into fragment tile vocabulary to
fix compatibility issue with Plone 5.1
[datakurre]

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- Fix issue where plone:tile -directive was not properly included
[datakurre]