stack: reuse call() for syntetic functions
stack: revise stack dumping code
stack: merge call() helpers into call()
stack: use TOP() macro instead of top()
stack: drop ntop(), use TOP(0) instead
stack: use POP() and PUSH() macros
stack: rename call_base() to bscall()
stack: fix stack poping in user API
stack: fix incorrect stack pushing
value: force type for conversion to depend on 1st argument of value_cmp()
stack: add support for comparison bscalls
stack: rename enum base to bscall
stack: add cleanup of acs_init()
stack: reduce family of argument bscalls
stack: rename extern_vars to global_vars
value: constify source argument of value_copy()