The rotation on a block model supports -45 to 45 only, with steps of 22,5.
This should be -180 to 180, according to the wiki. http://minecraft.gamepedia.com/Block_models
Proof: Download the resource pack and see stone is rotated 45 degrees. Change in the pack "angle" from 45 to 90, or any number outside of -45 to 45, in steps of 22,5.
I think this is a bug, but if it's intended, please add this.
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