accessibility fixes and minor css changes.

- added aria-hidden = "true" to prevent icons to be read by screen readers
- moved code on pages into "page-header" for better consistency

Change-Id: I3f497b2707991f7f628892a05734eea183a0d01d
Signed-off-by: Michael Davis <michael.s.davis@ibm.com>
diff --git a/app/common/styles/base/utility.scss b/app/common/styles/base/utility.scss
index 1131d82..91c60d5 100644
--- a/app/common/styles/base/utility.scss
+++ b/app/common/styles/base/utility.scss
@@ -95,6 +95,7 @@
   width: 0;
   position: absolute;
   overflow: hidden;
+  display: block;
 }
 
 .show-scroll {