Found in: /wiz/mimi/update/misc.c

Takes any arrays that are elements in arr and merges 
all of its elements as elements of arr.  Eg, decompose(({1,({2,3,}),4}))
will return: ({1,2,3,4}).  The algorithm is not recursive, so if any of
the arrays have arrays in them, those arrays remain intact.  Eg,
decompose( ({1,({({2,3}),4}),5}) )  returns:({1,({2,3}),4,5}).
See flatten_array for a recursive version.
