recreator: use standard stack for stacks

changed member stack and local stacks to standard stack
replaced push with emplace (uses template to forward arguments)
replaced pop function with pop string (no longer checks if empty)
replaced top function with individual functions for each stack variable
added top add parentheses for adding to string of top item
removed arguments from pop with parentheses (only string needed)
renamed stack is empty function to just empty (consistency with others)
renamed stack item variables using member notation
added stack item constructor with default arguments for emplace