Rename gr-admin-nav-behavior to admin-nav-util to preserve history

Change-Id: I02063e652da84c2dcfc1dc6e593c3ee22c4abda5
diff --git a/polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior.js b/polygerrit-ui/app/utils/admin-nav-util.js
similarity index 100%
rename from polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior.js
rename to polygerrit-ui/app/utils/admin-nav-util.js
diff --git a/polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior_test.js b/polygerrit-ui/app/utils/admin-nav-util_test.js
similarity index 100%
rename from polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior_test.js
rename to polygerrit-ui/app/utils/admin-nav-util_test.js