Add examples

For users, using the client is not intuitive and the documentation lacks of concrete examples. We need to provide simple and useful cases.

• Custom connection to Nuxeo
• Manage users (CRUD)
• Manage groups (CRUD)
• Manage documents (CRUD + lock)
• Manage repositories (CRUD)
• Manage permissions
• List tasks
• Set synchronization on a workspace and a folder
• Set up a proxy live
• Show helpers added to the client (operations attribute, server's configuration, checking access, etc.)
• Find duplicates documents on the server
• Log something server side
• Retrieve the log audit started from a given lower bound