Lowered fuzzy compare precision even more

Reason for that was that Matrix(m)*Matrix(m).inverse() == Matrix() shouldn't
fail with overprecision.

src/Math/constants.h

@@ -24,8 +24,8 @@ namespace Magnum { namespace Math {
 /** @brief Pi */
 #define PI 3.1415926535
 
-/** @brief Maximal tolerance when comparing doubles */
-#define EPSILON 1.0e-7
+/** @brief Maximal tolerance when comparing floats */
+#define EPSILON 1.0e-6
 
 }}