SSE2 optimisations for Spring SMT plugin

[Aaron]

Hi Everyone,

I've just ran a few tests on the SSE2-optimised version of the SMT plugin, and it's more than 10x faster than the non-SSE version. Consequently, I'll be adding the SSE2 version to the L3DT Pro installation package.

However, users should note that the SSE2 version will crash when used on computers that don't support SSE2. These include AMD processors before Athlon 64, and Intel processors before P4. Users of these older systems will have to use the un-optimised version of the plugin, which will still be included in the default installation, but not enabled by default.

Cheerio,
Aaron.