- for gcc4, insist on -fno-wrapv, since it breaks things.
- use atomic builtins as they are available (on i386 at least)
- remove a few reasons why gmake is required (but not all)
- pass MAKE_JOBS to configure step.
(ready for a gcc4 switch to enable webkit)
notice -phonon got scraped, because it becomes too hard to keep phonon out
of main qt tools way (like assistant on top of qtconfig)
