A modularisation + refactoring commit.  vg_execontext.c has been split into
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 a5019735-40e9-0310-863c-91ae7b9d1cf9
24 files changed