Change preloader to a light background (#899)

Author: SamCarlberg

ui/preloader/src/main/java/edu/wpi/grip/preloader/GripPreloader.java

@@ -18,8 +18,8 @@
 
 public final class GripPreloader extends Preloader {
 
-  private static final Color primaryColor = Color.gray(0.075);
-  private static final Color secondaryColor = Color.gray(0.1);
+  private static final Color primaryColor = Color.gray(0.925);
+  private static final Color secondaryColor = Color.WHITE;
 
   // Animation timings
   private static final double minTime = 1 / 3.0;

ui/preloader/src/main/resources/edu/wpi/grip/preloader/Preloader.css

@@ -1,3 +1,3 @@
 .root {
-    -fx-background-color: #111111;
+    -fx-background-color: #eee;
 }