If a call_list target function causes a slick-stack then Slick
can get into a bad state where it keeps calling this function and
the function keeps crashing.
For targets like "_switchbuf_" this can be unrecoverable.
This safe version of call_list keeps track - so if a function doesn't
return, it won't get called again -- instant recovery.
Restarting slickedit clears its memory of bad functions.
Added this to the git repo:
https://github.com/jporkka/slickMacros.git
