- changed registry format, adding the runtime dependency field

- changed registry format, adding the runtime dependency field
  (the idea is that for each pair <unit_name, md5sum> there are 3 dependencies
  information: dependency for development part of libraries, dependency for
  runtime part of libraries or non-custom bytecode binaries, version of the
  package shipping that unit)
- added command line flag --runtime
- added error when duplicate entries are found in registry at update time
- "dep" action no longer requires --package and --version arguments, it does
  not need them