Add Contact Refinement Parallax Mapping [ORL-48]

[orels1]

Based on this blog post:

https://www.artstation.com/blogs/andreariccardi/3VPo/a-new-approach-for-parallax-mapping-presenting-the-contact-refinement-parallax-mapping-technique

Sample implementation:

https://github.com/a-riccardi/shader-toy/blob/master/ShaderToy/Assets/Shaders/ParallaxOcclusionMapping.cginc

Should provide better results with potentially same or better performance

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Automatically created from Linear (#48)

via LinearSync

[orels1]

Based on this request: https://github.com/orels1/orels-Unity-Shaders/issues/42 (Had to re-create it because my linear-sync integration died there for a little)