Review admin ergonomics

• FIX: admin link on Firefox
• FIX: authentication on admin

Make each section scrollable

Fix AppBar z-index

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Allow to customize front page

• allow to override index.html
• separate admin from front

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• Documented how to add a new transformer
• Refactored transformers

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Document how to add new formats
Refactored formats

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Added documentation about adding new exporters
Refactored exporters
Updated Appbar

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Add instructions for adding a new parser.
Refactored parsers

FIX: déployment on EzMaster