pgsql: If we're going to advertise the array overlap/containment

Log Message:
-----------
If we're going to advertise the array overlap/containment operators,
we probably should make them work reliably for all arrays.  Fix code
to handle NULLs and multidimensional arrays, move it into arrayfuncs.c.
GIN is still restricted to indexing arrays with no null elements, however.

Modified Files:
--------------
    pgsql/src/backend/access/gin:
        ginarrayproc.c (r1.4 -> r1.5)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/ginarrayproc.c.diff?r1=1.4&r2=1.5)
    pgsql/src/backend/utils/adt:
        arrayfuncs.c (r1.130 -> r1.131)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/arrayfuncs.c.diff?r1=1.130&r2=1.131)
    pgsql/src/include/access:
        gin.h (r1.6 -> r1.7)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/access/gin.h.diff?r1=1.6&r2=1.7)
    pgsql/src/include/utils:
        array.h (r1.58 -> r1.59)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/utils/array.h.diff?r1=1.58&r2=1.59)