fix(timepicker): fixed issues and added some polish to timepicker shift back/forward buttons

public/app/features/dashboard/timepicker/timepicker.html

@@ -1,12 +1,12 @@
 <ul class="nav gf-timepicker-nav">
 
-	<li class="dashnav-move-timeframe gf-timepicker-time-control" bs-tooltip="'Shift time backward <br> (left-arrow key)'" data-placement="bottom">
+	<li class="dashnav-move-timeframe gf-timepicker-time-control" bs-tooltip="'Shift time backward <br> (left arrow key)'" data-placement="bottom">
 		<a ng-click='ctrl.move(-1)'><i class="fa fa-chevron-left"></i></a>
 	</li>
 	<li class="dashnav-zoom-out gf-timepicker-time-control" bs-tooltip="'Time range zoom in <br> CTRL+Z'" data-placement="bottom">
 		<a ng-click='ctrl.zoom(2)'>Zoom Out</a></li>
 	</li>
-	<li class="dashnav-move-timeframe gf-timepicker-time-control" bs-tooltip="'Shift time forward <br> (right-arrow key)'" data-placement="bottom">
+	<li class="dashnav-move-timeframe gf-timepicker-time-control" bs-tooltip="'Shift time forward <br> (right arrow key)'" data-placement="bottom">
 		<a ng-click='ctrl.move(1)'><i class="fa fa-chevron-right"></i></a>
 	</li>