Add error messaging for error log date filtering and Safari support

- Updated filters to use semantic markup (fieldset)
- Added check for input date type support and updated
  expected date format to the legend
- Added error message if date format is invalid
- Updated layout to support error message

Tested the changes in the following browsers:
- Safari
- IE 11
- Chrome
- Edge
- Firefox

Signed-off-by: Derick Montague <derick.montague@ibm.com>
Change-Id: If0b874644b80640dc5bfd8211459c012807ea492
diff --git a/app/server-health/styles/log.scss b/app/server-health/styles/log.scss
index 301dc2c..bb5fc69 100644
--- a/app/server-health/styles/log.scss
+++ b/app/server-health/styles/log.scss
@@ -36,6 +36,7 @@
   }
 }
 
+// Event Filter
 #event-filter {
   .filter-label {
     color: $text-02;
@@ -47,7 +48,6 @@
   .event__severity-filter {
     margin-right: 2em;
     margin-bottom: 1em;
-    font-size: 0.9em;
     .btn {
       width: 100px;
       float: left;
@@ -63,10 +63,6 @@
     input {
       width: 170px;
     }
-    label {
-      height: 0;
-      text-indent: -9999px;
-    }
   }
   .event__status-filter {
     float: left;
@@ -81,6 +77,30 @@
   }
 }
 
+.event-filter__content {
+  display: flex;
+  flex-wrap: wrap;
+  align-items: flex-start;
+  margin-top: 1em;
+
+  > fieldset {
+    flex: 0 0 auto;
+  }
+
+  .error {
+    margin-bottom: 0;
+  }
+}
+
+.event__date-filter-content {
+  display: flex;
+  align-items: flex-start;
+}
+
+.event__date-filter-divider {
+  margin: .25rem .5rem 0 .5rem;
+}
+
 .event-log__filters {
   position: relative;
   padding-bottom: 0.5em;