Improved pkg best matching in rpool, and support for exact pkgver matches.

- xbps_repository_pool_find_pkg in best match case, now returns the
  newest package version available in rpool.
- Added xbps_repository_pool_find_pkg_exact that returns a package
  by exact matching a pkgver.
- Removed xbps_handle_alloc(), the user is free to use memory
  allocated from heap or stack.
- Improved API documentation in preparation for 0.12.

Bumped XBPS_API_VERSION again.

include/xbps_api_impl.h

@@ -1,5 +1,5 @@
 /*-
- * Copyright (c) 2010-2011 Juan Romero Pardines.
+ * Copyright (c) 2010-2012 Juan Romero Pardines.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -184,12 +184,6 @@ prop_dictionary_t HIDDEN
 	xbps_find_virtualpkg_conf_in_dict_by_pattern(prop_dictionary_t,
 						const char *,
 						const char *);
-/**
- * @private
- * From lib/init_virtual_pkgs.c
- */
-void HIDDEN xbps_init_virtual_pkgs(struct xbps_handle *);
-
 /**
  * @private
  * From lib/cb_util.c
@@ -201,6 +195,12 @@ void HIDDEN xbps_set_cb_state(xbps_state_t, int, const char *,
 void HIDDEN xbps_set_cb_unpack(const char *, int64_t, ssize_t,
 			       ssize_t, bool, bool);
 
+/**
+ * @private
+ * From lib/package_unpack.c
+ */
+int HIDDEN xbps_unpack_binary_pkg(prop_dictionary_t);
+
 __END_DECLS
 
 #endif /* !_XBPS_API_IMPL_H_ */