make filter panel thinner

Making the filter panel thinner by 18%. To do this
we moved the date range next to the query box.
The thinner filter box gives us more width for the plot.

pdb-js/src/app/visualization-page/visualization-page.component.scss

@@ -12,9 +12,9 @@
     height: 100%;
     margin: 0;
     grid:
-      "query-box query-box" auto
-      "filters results" 1fr
-      / 24em 3fr;
+      "query-box query-box date-box" auto 
+      "filters results results" 1fr
+      / 19.7em 3fr 21em;
   }
 }
 
@@ -24,6 +24,7 @@
     margin: 0;
     grid:
       "query-box" auto
+      "date-box" auto
       "filters" auto
       "results" 1fr
       / 1fr;
@@ -35,7 +36,12 @@
 
 #query-box {
   grid-area: query-box;
-  margin: 1em;
+  margin: 1em 0.5em 0.5em 0.5em;
+}
+
+#date-box{
+  grid-area: date-box;
+  margin-right: 1em;
 }
 
 #filters {
@@ -43,15 +49,15 @@
 }
 #filterpanel {
   background-color: #f8f8f8;/*#fafafa;*/
-  padding: 1em;
-  margin: 0 1em 1em 1em;
+  padding: 0.5em;
+  margin: 0 0.5em 0.5em 0.5em;
   border-radius: 5px;
 }
 
 #results {
   grid-area: results;
   overflow: hidden;
-  margin-right: 1em;
+  margin-right: 0.5em;
   position:relative; /* ??? */ 
 }