Revert "Changing to use getComputedStyle and putting the filter in the CSS instead of using the style attribute."

This reverts commit 8a7c941855270470c5b188de107f2dffa6690528.
Adding a transition effect.
Uh-oh. Mystery change.
Resolving a conflict.
Merge branch 'gh-pages' of github.com:webinista/TinkeringWithCSSFilterEffects into gh-pages

Mystery pull
Changing brightness to 1 on load.
Changing default form value of 'brightness' to match previous commit.
Rewriting to use CSSOM where possible.