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.
Since the <query> node results in the generation of a "blueprint"
report, it should better be named <blueprint>. This also clears the way
for adding further query types such as <dependencies>, following the
same pattern of generating a report of the corresponding query name.
This patch changes the depot layout such that each archive is
represented as a directory that contains the versions of the archive as
subdirectories.
Issue #2610
