SUP-258, Change button text to say Join Us instead of Sign up

Author: vikasrohit

src/js/app/my-dashboard/partials/member-program.html

@@ -15,7 +15,7 @@
     </div>
     <div class="signup">
       <!-- used style as workaround to override display property -->
-      <input type="button" class="btn btn-primary center-block block-display" value="Join" style="display:block;" ng-click="vm.registerUser()">
+      <input type="button" class="btn btn-primary center-block block-display" value="Join Us" style="display:block;" ng-click="vm.registerUser()">
     </div>
   </div>
   <div rel="registered-view" ng-show="!vm.loading && vm.registration">