Changes to Instructions

| old            | new                   |
|:---------------|:----------------------|
| pop            | takes arg 1 <= n <= 5 |
| divine         | takes arg 1 <= n <= 5 |
| read_mem       | takes arg 1 <= n <= 5 |
| write_mem      | takes arg 1 <= n <= 5 |
| hash           | pops 5                |
| divine_sibling | pushes 5              |
| assert_vector  | pops 5                |
| sponge_absorb  | pops 10               |
| sponge_squeeze | pushes 10             |
| xxadd          | pops 3                |
| xxmul          | pops 3                |
| read_io        | takes arg 1 <= n <= 5 |
| write_io       | takes arg 1 <= n <= 5 |