Core: dynamically resize weight table

Replace the fixed-size weightsystem table by a dynamically
relocated table. Reuse the table-macros used in other parts
of the code.

The table stores weightsystem entries, not pointers to
weightsystems. Thus, ownership of the description string is
taken when adding a weightsystem. An extra function adds
a cloned weightsystem at the end of the table.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

core/parse.h

@@ -54,7 +54,7 @@ struct parser_state {
 	bool in_settings;
 	bool in_userid;
 	struct tm cur_tm;
-	int cur_cylinder_index, cur_ws_index;
+	int cur_cylinder_index;
 	int lastcylinderindex, next_o2_sensor;
 	int o2pressure_sensor;
 	int sample_rate;