Trac #13849

Increased the maximum possible texture & renderbuffer size to 16384 (the minimum required for DX11 cards).
Limit the actual maximum texture & renderbuffer size to the maximum
that it reported by the underlying D3D9 device.

Note that creating textures and renderbuffers at the maximum size will quickly exhaust video memory!

Signed-off-by: Nicolas Capens

git-svn-id: https://angleproject.googlecode.com/svn/trunk@447 736b8ea6-26fd-11df-bfd4-992fa37f6226