Compilation fix. MVS 2013 doesn't support constexpr and it's not needed either.

lib/mapObjects/CGHeroInstance.h

@@ -64,9 +64,9 @@ public:
 	ConstTransitivePtr<CCommanderInstance> commander;
 	const CGBoat *boat; //set to CGBoat when sailing
 
-	static constexpr ui32 UNINITIALIZED_PORTRAIT = -1;
-	static constexpr ui32 UNINITIALIZED_MANA = -1;
-	static constexpr ui32 UNINITIALIZED_MOVEMENT = -1;
+	static const ui32 UNINITIALIZED_PORTRAIT = -1;
+	static const ui32 UNINITIALIZED_MANA = -1;
+	static const ui32 UNINITIALIZED_MOVEMENT = -1;
 
 	//std::vector<const CArtifact*> artifacts; //hero's artifacts from bag
 	//std::map<ui16, const CArtifact*> artifWorn; //map<position,artifact_id>; positions: 0 - head; 1 - shoulders; 2 - neck; 3 - right hand; 4 - left hand; 5 - torso; 6 - right ring; 7 - left ring; 8 - feet; 9 - misc1; 10 - misc2; 11 - misc3; 12 - misc4; 13 - mach1; 14 - mach2; 15 - mach3; 16 - mach4; 17 - spellbook; 18 - misc5