implement remote building ability activation

[hervan]

first step is to refactor a testPattern(...) - it's already implemented inside build(...), but it will be entirely reused for this mechanic. consider whether to include meeple side flipping in it, as it's also useb by both, but then maybe it must come before regular exploration (because pattern rotation and flipping only rotate around tile at (0, 0)).

side flipping is necessary among other things because these powers will usually be stronger than those given by local building power activation (also to be implemented). they further require a different geography than the originating building (require the building to be placed in the same geography its blueprint was acquired).

finally, if every stat of players and their units can be "powered up", one approach to turn all these stats improvements into powerups is to enable them through combos - the harder the combo, the better the benefit:

• if handling all the combinations is overwhelming, a valid solution is to turn them into a deck of cards with balanced benefits - actually, a deck for each level of benefits.
• otherwise, tell which combination gives each powerup - leaving some combinations out can yield a more asymmetric mechanic.
• or specify what are the basic combos, and above them reward exponential benefits - 4 activations receive 4 times each powerup? if it's too overpowered, 1-2-2-3-3, where making a 3-combo with the same multiplier of a 2-combo is still prefered because the alternative is to make 2x2 + 1x1, not getting a multiplier for the third activation.
• an initial list of benefits is available in code comments, but complement it with every other "power-uppable" stat.

[hervan]

if combos are adopted, remove benefit from "hold" - now it gives +1 resistance, make it a simple skip.

[hervan]

modifiers for the special powers:

• strength
• resistance
• faith
• speed
• resource gathering
• resource trading

thematic powers:

• bomb over a region
• events
  • something that a city gives to everything on its terrain
  • something activated for the current terrain