Animation: use float literals everywhere.

Makes it easier to copypaste into GLSL ES.

src/Magnum/Animation/Easing.h

@@ -731,7 +731,7 @@ Combination of @ref circularIn() and @ref circularOut().
 @see @ref sineInOut()
 */
 inline Float circularInOut(Float t) {
-    if(t < 0.5f) return 0.5f*(1.0f - std::sqrt(1.0f - 4*t*t));
+    if(t < 0.5f) return 0.5f*(1.0f - std::sqrt(1.0f - 4.0f*t*t));
     return 0.5f*(1.0f + std::sqrt(-4.0f*t*t + 8.0f*t - 3.0f));
 }