Account now has Wallets and Communities
Wallets are now managing the network side of ucoin
A community doesnt depend anymore on a wallet
A wallet knows what community it is part of thanks to currency name

Adding unit tests for community

Refactoring
Debugging

Configuring account : changing its name and the communities

Sauvegarde de fichier, utilisation de "factory" pour créer des models a partir de rien ou a partir de json.