To support off-loading the running of configuration mode scripts (for daemon or testing), it is useful to allow initialization of Config from data other than a call to the Vyatta backend; for example, from raw config strings. The PR linked below provides classes ConfigSourceSession(ConfigSource) and ConfigSourceString(ConfigSource) to allow that generalization.

The default behaviour will use ConfigSourceSession, which encapsulates the current init method; no changes to current code are required.