Add dedicates Froggit page

Add Froggit dedicated page like this example

• review text on this page @cchaudier
• review text on this page @michel-thomas
• Add dedicated froggit this the content of this page @Plumtree3D
• Add dedicated link on admonition between plans and TARIFS DE LANCEMENT on price page @Plumtree3D
• Add Offres et Tarifs section on footer, see example on this site @Plumtree3D
• On Offres et Tarifs section add link to tarifs, dedicated @Plumtree3D