stun: minimal working client/server

pkg/c3/motes.h

@@ -998,6 +998,7 @@
 #   define c3__sard   c3_s4('s','a','r','d')
 #   define c3__sav    c3_s3('s','a','v')
 #   define c3__save   c3_s4('s','a','v','e')
+#   define c3__saxo   c3_s4('s','a','x','o')
 #   define c3__scam   c3_s4('s','c','a','m')
 #   define c3__scan   c3_s4('s','c','a','n')
 #   define c3__scry   c3_s4('s','c','r','y')
@@ -1111,6 +1112,7 @@
 #   define c3__ston   c3_s4('s','t','o','n')
 #   define c3__stop   c3_s4('s','t','o','p')
 #   define c3__stub   c3_s4('s','t','u','b')
+#   define c3__stun   c3_s4('s','t','u','n')
 #   define c3__stur   c3_s4('s','t','u','r')
 #   define c3__sub    c3_s3('s','u','b')
 #   define c3__sunt   c3_s4('s','u','n','t')