Make collision code placement more like original (+ small fixes)

# Conflicts:
#	premake5.lua
#	src/CMakeLists.txt
#	src/collision/Collision.cpp
#	src/core/Collision.h

src/collision/ColBox.cpp

@@ -0,0 +1,21 @@
+#include "common.h"
+#include "ColBox.h"
+
+void
+CColBox::Set(const CVector &min, const CVector &max, uint8 surf, uint8 piece)
+{
+	this->min = min;
+	this->max = max;
+	this->surface = surf;
+	this->piece = piece;
+}
+
+CColBox&
+CColBox::operator=(const CColBox& other)
+{
+	min = other.min;
+	max = other.max;
+	surface = other.surface;
+	piece = other.piece;
+	return *this;
+}