Kernel changes:
* Add IP_FW_OBJ_FLUSH opcode (flush table based on its name/set)
* Add IP_FW_OBJ_DUMP opcode (dumps table data based on its names/set)
* Add IP_FW_OBJ_LISTSIZE / IP_FW_OBJ_LIST opcodes (get list of kernel tables)
Userland changes:
* move tables code to separate tables.c file
* get rid of tables_max
* switch "all"/list handling to new opcodes