Move Travis onto llvm-3.3

[staticfloat]

This updates Travis to use LLVM 3.3 instead of 3.2, and simultaneously heralds the arrival of 3.3 binaries on the PPA. 3.2 binaries are maintained alongside, so users can switch at their leisure, for now.

@JeffBezanson; do you want to move to 3.3 for the 0.2 release? I can't find a reason not to, we have a PPA, Homebrew has a formula, and even Arch Linux has a package for it, so I don't think we're going to lack in distribution support. If so, we can merge this, I'll change my nightlies to require 3.3 instead of 3.2, and we can change the requisite setting in deps/Version.make. We just have to be careful to clear out anything having to do with LLVM in usr/ after the version is changed in deps/Version.make.

[ViralBShah]

It would be nice to move to llvm 3.3. I know it is late in the release process, but we still have another 2-3 weeks of the release period ahead of us, and the freeze is not yet on.

I would be more conservative once we have more releases and a larger user base. This also fixes some open issues related to LLVM, which makes it more desirable.

[JeffBezanson]

Yes, I'm in favor of this since it fixes a specific bug.

[ViralBShah]

Can you go ahead and update the LLVM_VER?

[JeffBezanson]

Hey uh, @loladiro @vtjnash do you remember which bug(s) llvm 3.3 fixes for us?

[Keno]

AVX feature detection (#3634)

[JeffBezanson]

Ah, the issue was already closed, which is why I wasn't finding it.

[staticfloat]

Note this also affected select EC2 users.

[Keno]

Only the ones in Ireland though (Remember the "Julia crashes in Ireland" issue? - Same problem but LLVM not OpenBLAS).