- first part of the "inject-local-packagedata" patch

- first part of the "inject-local-packagedata" patch
- rewrote readdeps():
  * it parses build's current internal format (which is created by the create*deps scripts)
  * it expects a self-provides entry for each package
  * the $pkginfo hashref can be used to store additional information (version, release, arch)
  * at the moment it does not support different architectures per file (because we don't need it)