Don't use std::min/max in mid()

VC++'s optimizer completely falls down on it for whatever reason.

src/utils.h

@@ -80,7 +80,9 @@ template <typename T> T tabs(T x) { return x < 0 ? -x : x; }
 
 /// Get the middle value of a, b, and c (i.e. clamp b to [a,c])
 /// @precondition a <= c
-template<typename T> inline T mid(T a, T b, T c) { return std::max(a, std::min(b, c)); }
+template<typename T> inline T mid(T a, T b, T c) {
+	return a > b ? a : (b > c ? c : b);
+}
 
 /// Get the text contents of the clipboard, or empty string on failure
 std::string GetClipboard();