Counter Bounds Pushing/Popping

[michael-butler]

Need system to push counter object's bounds when entering an _if block and pop them when leaving corresponding block. System also needs to combine their results when entire block (if... else) is finished. This is to resolve the issue:

_if ( cond1 ) [
dc1 << dc2[-2..2] + dc3[0..5],
_else,
dc1 << dc2[-2..2] - dc3[0..5],
]

dc1 should have range of [-7..7] at the end of this block instead of the most recent answer [-2..7].