GitLab

The class is renamed to "SessionHelper" and moved to
"agkyra.protocol". It uses the session database to get information
about the status of the protocol server.

The session database is used to store the address and ui_id of the
protocol server as well as a time stamp. The helper uses this
information to resolve if the protocol server is active. If the
server is active, the helper assumes there is a session running and
allows the client to use the session credentials to connect to it.
Otherwise, it generates new session credentials and offers the
ability to start a protocol server.

The GUI class is also modified to raise an assertion error if
another GUI is already running. This is resolved by comparing the
session information stored in the session file with the one
provided by the helper. If they match, a GUI is running, otherwise
a new GUI is launched.

The mechanism is based on syncing message consumption, which works
only while the client is syncing (therefore, not in paused mode).

When GUI consumes a "SyncMessage", an "unsynced" counter is
increased, while a "AckSyncMessage" causes a "synced" counter to
increase. The two counters are pushed to GUI regularly enough.

This patch refers to the settings update on closing the settings
window.

This patch is related to the endpoint URLs needed to make various
UI operations i.e., login and vising the pithos page on a browser.

The helper used to provide the GUI with all URLs necessary, while
now they are retrieved by the GUI itself, with the tokenless
request "POST <auth_url endpoint>/tokens".

Settings are loaded and updated in protocol.py
If the client is not ready yet, some GUI options are not gray
and unclickable until the client is ready.

Also, create an application token, unique for each run