sc2: Dark Templar War Council Upgrades - Shadow Fury

[MatthewMarinets]

Added Dark Templar War Council Upgrades -- Shadow Fury.

Shadow Fury is so strong I decided to split it in two. The "Lesser" variant gives 2 strikes, the "Greater" one gives 3.

Progress on #152 Pairs with client PR #247

Without upgrade:

With Greater only:

With Lesser only:

With both:

• Tested all cases output the correct number of slashes and reappeared / became vulnerable again after the last slash.
• Tested unlocks work with client /send commands

TODO

• [x] Add unlock triggers
• [x] Test with client

[MatthewMarinets]

Just realized this likely breaks predator shadow fury -__-

I'm in favour of removing predator shadow fury to replace it with a different upgrade. The alternative is to split the relevant parts of the predator ability, which I think just involves splitting 2 effects and a behavior