New dependency/install/unpack WIP code.

This implementation will be faster and resolv the dependency chain
correctly taking into account indirect/direct deps and priority.

--HG--
extra : convert_revision : cc4ec186f06f944fa8825b176344c4d612658f85

include/plist.h

@@ -57,7 +57,7 @@ xbps_callback_array_iter_in_dict(prop_dictionary_t, const char *,
  * Returns the package's dictionary object, otherwise NULL.
  */
 prop_dictionary_t
-xbps_find_pkg_in_dict(prop_dictionary_t, const char *);
+xbps_find_pkg_in_dict(prop_dictionary_t, const char *, const char *);
 
 prop_dictionary_t
 xbps_find_pkg_from_plist(const char *, const char *);