perlcalls: simple extraction of subroutine call structure.

Usage: perlcalls <options> <perl_script>

Options:
	-a	Try to add the ampersand to the sub calls...

	-o	Print the calls from one sub only once,
		instead of once per call. In this case
		the calling parameters are not printed.

	-v	Verbose. Print out calls to perl builtin
		functions as well. You will usually want
		to use -o as well since the output gets
		large in this case.

	-nr	Do not follow "requires".

	-s	Only print the subroutines found, not
		the calling structure.

	-t	Trim off '&', ':', and (...) from names and
		do not print out the "calls:" lines.

	-m <list> Match subroutine names in comma separated
		  <list> only. Use -M <list> to still get the
		  &name() calls, or -v to still get the keywords.

	-h	Print this help.

Notes:
	This is not a true perl parser, so can easily
	be fooled or confused.

	Quoting is mostly ignored. Block quotes: <<"END";
	are attempted.
	Nested () are not explored.
	Only one level of "require" is searched.
	Eval-ing a subroutine name or definition wont be noted.

	Requires same indentation for sub line and matching }
		sub foo {
			...
		}

	Requires perl4 style sub calls: &foo(...) not foo(...)
	(perl5 style could be added with a second pass...)