Fix: Tweaked color of search button

Made it less saturated since some users felt the
bright green color to be a bit distracting.

http://i.imgur.com/XdBrQpb.png

Change-Id: I9733b9a9c8ff536e64a6332362135e37a2de4df8
diff --git a/gerrit-gwtui/src/main/java/com/google/gerrit/client/gerrit.css b/gerrit-gwtui/src/main/java/com/google/gerrit/client/gerrit.css
index 7995eeb..20fc645 100644
--- a/gerrit-gwtui/src/main/java/com/google/gerrit/client/gerrit.css
+++ b/gerrit-gwtui/src/main/java/com/google/gerrit/client/gerrit.css
@@ -310,7 +310,7 @@
   color: #FFF;
   border-color: rgba(0, 0, 0, 0.15);
   height: 14px;
-  background-color: #20CA60;
+  background-color: #53A93F;
   -webkit-border-radius: 2px;
   -webkit-box-sizing: content-box;
 }