This patch changes the 'depot_deploy' tool to spawn any number of
runtimes. In contrast to the original version, which merely consumed a
blueprint generated by a pre-configured 'depot_query' instance, the new
version actively generates queries as needed. So there is a feedback
loop between 'depot_deploy' and 'depot_query'. The instantiation of
subsystems is controlled by the '<start>' nodes of the 'depot_deploy'
configuration. For each start node, the tool tries to determine the
ingredients (provided by the depot) by asking the 'depot_query' tool.
Once the information is complete, a corresponding start node of the
dynamic init instance is generated.