Stack tracing

Note: I wasn't able to cherry-pick this from Peter, he's the actual
author of this code (59747ae7d2924bbb3973754e683b8ab2226cba68)
Smarter stack tracing by following update frames
Add reifyStack# primop
Refactor out countStackSize()
Allow the primitives for GHC.ExecutionStack

There's still work left. In particular the Dwarf functions should call
dwarf_init() by themselves. This is to simplify the Haskell API later
on. Also dwarf_init() have to change, so that calling it twice has no
effect.

NOTE: 5 Feb 2014: I "fixuped" the delete commits later, and now
this should be an empty commit, but isnt due to the shit that
I committed aswell when I first commited
Add dwarf_dump_units

Conflicts:

	rts/Dwarf.c
Fix bug in stgAllocArrWords
Stop recurse, just return
Make code more readable
Files I dont wanna loose DONT MERGE
Change dwarf_lookup_and_write

Hoping to making it suitable for a primop
Add dwarf_ensure_init()

Note: the name "dwarf_init()" is taken by libdwarf
Add dwarf debug_info count function
Fix formatting
Fix
Publisize Dwarf.h

Rest of old commit messages:

Make a public dwarf interface

PUBLIC_DWARF_UNIT_MEMBERS

Publisize Dwarf.h

Conflicts:

	rts/Dwarf.h
Improvments to .env

Update .env file

Improve .env

.env
Change stop recurse policy
Add GNU no_return attribute

Seems needed for my compiler it seemed. I lost the irc log, dammit
Ensure we initialize dwarf on calls