qpkg: added some field names and relational operators from Ubuntu

- gobble.c (gobble_buf): recognize (and ignore) the following fields:
  Bugs, Installed-Size, MD5sum, Origin, Original-Maintainer, SHA1, SHA256,
  Task.
- pkg.h (enum relop): added comments showing the respective symbol
- pkg.h (enum relop): added rel_gg (>>), rel_le (<=), and rel_ll (<<)
- gobble.c (gobble_buf): recognize >>, <=, and <<
- TODO: record progress in support beyond Jlime/OE

qpkg/pkg.h

@@ -28,9 +28,12 @@ enum flags {
 };
 
 enum relop {
-	rel_eq,
-	rel_ge,
-	rel_lt,
+	rel_eq,		/* =  */
+	rel_ge,		/* >= */
+	rel_gg,		/* >> */
+	rel_lt,		/* <  */
+	rel_le,		/* <= */
+	rel_ll,		/* << */
 };
 
 struct pkg;