Fallback servers #1
Description
In many use cases, it does not matter which timestamping server provides the timestamp, but just that any timestamp is added. Currently, the only way to achieve this is by specifying several servers, which are all tasked with creating a timestamp.
It should be possible to obtain a single timestamp from a list of servers, selected from a list of servers, typically from the first one which is reachable.
Many options
Provide --only-one, --only=NUMBER, --random, and --coalesce options to select 1 or N from the server list, either in order or at random, into traditional per-server branches or a single, coalesced branch.
Few options
Depart from the existing model of per-server branches. Instead, use a single timestamp branch and stop after the first server (with the server list being larger). If the traditional (=current) behavior is desired, add a --all option (required e.g. for timestamping servers).
Preference/transition
I currently favor the few options approach. In a transition period, when there is no timestamps branch, it will be forked from e.g. gitta-timestamps to provide a seamless transition.