sample points half sphere maybe bugged

[soraphis]

https://github.com/soraphis/Unity-Post-Processing-Effects/blob/master/Assets/SSAO/SSAO.shader#L86

i think

if( dot(normal, sample) < 0.0f) sample *= -1.0f;

should be:

if( abs(dot(normal, sample)) < 0.0f) sample *= -1.0f;