fix write/seek semantics for Z buffers

add sort function

add new value type: hashes
@TYPE OF hash : "hash"
- create:
@TAN list; #<key1 value1 key2 value2#>
@SIN list; #<key1 key2#>
@COS list; #<value1 value2#>
- decompose:
@ATAN hash; -> #<key2 value2 key1 value1#>
@ASIN hash; -> #<key2 key1#>
@ACOS hash; -> #<value2 value1#>
- push entries:
hash + hashmod
- pop entries:
hash - hashmod
- replace (-+) entries:
hash _ hashmod
- index:
hash . key
- slice:
hash . #<key1 key2#>
- remove:
hash % key
hash % #<key1 key2#>
- get depth:
hash / key