#574: More exessive memory usage

I've been thinking about building a library interposer (in the spirit of http://developers.sun.com/solaris/articles/lib_interposers.html) that will track malloc / realloc / calloc by script line (pull the top frame out of g_frame_stack) and script file; I envision using SIGUSR1 and SIGUSR2 to dump and clear gathered statistics, respectively.

I tried to do something similar with systemtap, but I wasn't able to keep bro running fast enough to process nontrivial volumes of live traffic. Haven't tried dtrace yet.

If this sounds like something that'd be useful here, I can inject it into the top of the TODO.