Pull releases

One folder per pull request, with a README whose first line is the PR title.

#	PR	Branch
001	First version of the site	feature/first-site
002	Add link previews	feature/link-previews
003	Use the name MPCkit	feature/mpckit-casing
004	Add a features card for native, small and offline	feature/native-offline-card
005	Update the site for MPCkit 0.5.3	feature/0-5-3-update