* move AccountSettings up to package context
* HttpClient: take authentication from AccountSettings in the constructor
* App: provide global instance of MemorizingTrustManager
* App: provide global Java logger, optionally with verbose and external file logging
* LoginCredentials: moved from inner-class into setup package
* HttpClient: authentication that is limited to a host name is never preemptive
* DavResourceFinder: service configuration == null means that this service is not available
* new SQLite database for CalDAV/CardDAV services
* added AccountDetailsFragment, which asks for account name and then finishes account creation
* updated AccountListFragment