Redstone wire uses different criteria for connecting visually and logically

The bug

Redstone wire in some situations uses different logic for connecting visually (in which direction the dust texture goes) and logically (what gets powered).

Affected situations

List might be incomplete
Last updated for 18w05a

Glowstone should possibly not show redstone wire on its side since all other blocks which only transfer a redstone signal upwards have no wire on their side.

Code analysis and suggested fix

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