Add D3D version and shader models to renderer string reported by GetString.

It looks like this now:
ANGLE (NVIDIA Quadro 600 Direct3D9Ex vs_3_0 ps_3_0)

I also noticed that the strings returned by GetString are not all static so I fixed that as well.
Review URL: https://codereview.appspot.com/7068058

git-svn-id: http://angleproject.googlecode.com/svn/trunk@1646 736b8ea6-26fd-11df-bfd4-992fa37f6226
Update version.
Review URL: https://codereview.appspot.com/7062061

git-svn-id: http://angleproject.googlecode.com/svn/trunk@1647 736b8ea6-26fd-11df-bfd4-992fa37f6226