Reexport IT_INSERT for array.

Even it is slow, it may be useful.

m-array.h

@@ -72,6 +72,7 @@
    ,IT_PREVIOUS(M_C(name,_previous))					\
    ,IT_REF(M_C(name,_ref))						\
    ,IT_CREF(M_C(name,_cref))						\
+   ,IT_INSERT(M_C(name,_insert))                                        \
    ,IT_REMOVE(M_C(name,_remove))                                        \
    ,CLEAN(M_C(name,_clean))						\
    ,PUSH(M_C(name,_push_back))						\