two halves: stacktrace.c, which deals with getting, traversing and printing
stack traces; and execontext.c, which deals with storing stack traces
permanently in a way that avoids duplicates, and comparing them.
One nice outcome: previously we were often creating ExeContexts, which live
forever, even when they were only needed temporarily. Ie. this was a memory
leak, which has been removed.
As part of this, new headers have been created, carved off core.h and
tool.h. Lots of function names have changed, too.
In Massif, I also changed a lot of "eip" names to "ip" to make them less
x86-specific.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@3429
