Allow to have the server information without using the async storage

When we need the server name or version, we always rely on the async storage to get them (loginInfo stuff).

We could improve that by storing the information we need in a new serverInfo module that we can import wherever we need that information.
It removes some complexities:

• no more async function when not needed
• easily retrieving the server name when managing theme (without getting it from the nuxeo._baseURL property ...)