Reduce size of Bonus struct from 320 bytes to 296 bytes.

- Internal enums were resized to occupy single byte.
- Duration bitmask uses 16 bit integer directly instead of std::bitset<11> which consumed 8 bytes.
- Fields shuffled to minimise padding and keep the most useful data on first 2 cache lines.

server/battles/BattleActionProcessor.h

@@ -19,7 +19,7 @@ class CBattleInfoCallback;
 struct BattleHex;
 class CStack;
 class PlayerColor;
-enum class BonusType;
+enum class BonusType : uint8_t;
 
 namespace battle
 {