Rework Aether Permeation prodigy

[Flitvious]

As it is now, Aether Permeation prodigy doesn't work and here's why:

1. Multiplier is bugged. The 0.66 multiplier applies to the final result, not to the replaced elemental resistances. This is unexpected and is probably a bug. If you are hit, for example, by fire and your arcane resistance is 70%, you would think that the actual elemental resistance will be 0.66 of that, 46%. This is not so. Full 70% resistance value is used, your resist_all value is factored into the formula, and then the 0.66 multiplier is applied to the total result. This breaks everything. Say, for example, you managed to obtain unrealistic 100% resist_all and 100% arcane resistance. You still get 66% resistance in the end, not 100% as you would expect in this case.

2. Resistance cap is indirectly multiplied. Your existing elemental resistances are forever replaced by lower values and cannot be raised afterwards by any means. Offered resistance cap and arcane resistance do not help. The problem here is that the multiplier indirectly affects the maximum possible resistance cap for all non-arcane damage. I will try to explain what I mean. There are only two items in the game that raise arcane resistance cap. First is Aetherwalk artifact boots, it gives 5%. Second is "protective" amulet that raises resistance caps by another 2-5%. All in all, you can theoretically get to 90%. That would be nice, if not for .66 multiplier. Even if the multiplier would work as expected (and it doesn't, see above), the maximum non-arcane elemental resistance you could get is not 90% but 0.66 of that, about 60%. See, the arcane resistance cap is also multiplied along the way. For example, once you get the prodigy, your resistance to fire damage can never get above 60%. Fire resistance cap cannot affect this. Massive stacking of arcane resistance gear cannot affect this. Higher's racial power and Arcane Power talent cannot affect this. As a result, you become forever and irrevocably vulnerable to all non-arcane attacks and have no possible way of better mitigating any non-arcane damage. Say you want to better protect yourself against fire. You have literally zero options. The 80-90% cap on arcane becomes 50-60% cap on everything else.

Possible ways to fix these problems:
1. Fix the multiplier bug. It must apply to the replaced value, not to the final result. This can fix problem #1, but not #2.
2. Remove the multiplier. Resist_all will work as expected. Resistance cap mechanic will care about the rest. Drop the cap bonus from the prodigy if the result is too OP. This fixes #1 and #2.