Revert "Make inner whitespace nuke consistent with loops."

This reverts commit 1a30396d30f6875b4e541de7736b5316dcbe79dc.
Fix test for nuke_inner_whitespce and loops
Add test for scripts and nuke_inner_whitespace
Fix rstrip_buffer! and scripts

Make rstrip_buffer! emit `_hamlout.rstrip!` when the last thing in the
output was a script. In general there is no way to determine what the
script outputs, so we need to defer to a render time call to `rstrip!`.
Remove check for nuke_inner_whitespace

Remove superfluous checks for nuke_inner_whitespace in push_script.

This option is only set on tag nodes. Any tag node with a script has
the in_tag option set, so this test isn't needed.