Refactor, separate docs from headers, add ru docs

Doxygen kind'a sucks and I need multilanguage documentation, so I did
that. Also, separated massive Math.h file into smaller files.

include/BH/Math/Vec3i.h

@@ -0,0 +1,53 @@
+#ifndef BH_MATH_VEC3I_H
+#define BH_MATH_VEC3I_H
+
+#include "../Common.h"
+
+void BH_Vec3iAdd(const int a[3],
+                 const int b[3],
+                 int out[3]);
+
+
+
+void BH_Vec3iSub(const int a[3],
+                 const int b[3],
+                 int out[3]);
+
+
+
+void BH_Vec3iMul(const int a[3],
+                 const int b[3],
+                 int out[3]);
+
+
+
+void BH_Vec3iScale(const int a[3],
+                   int b,
+                   int out[3]);
+
+
+
+void BH_Vec3iMulAdd(const int a[3],
+                    const int b[3],
+                    const int c[3],
+                    int out[3]);
+
+
+
+void BH_Vec3iNegate(const int in[3],
+                    int out[3]);
+
+
+
+void BH_Vec3iMin(const int a[3],
+                 const int b[3],
+                 int out[3]);
+
+
+
+void BH_Vec3iMax(const int a[3],
+                 const int b[3],
+                 int out[3]);
+
+
+#endif /* BH_MATH_VEC3I */