Second commit of dark theme changes form UD - issue sakaicontrib#94

SAKAI-5974 Add new theme-independent sort icons, add theme to datepicker

tool/src/webapp/css/attendance.css

@@ -56,7 +56,7 @@ div.table-responsive {
 }
 
 h1.overviewHeader, h1.itemsHeader, h1.settingsHeader, h1.gradingHeader {
-    color: #555;
+    color: var(--sakai-text-color-1);
     margin-top: 1.2em;
     min-height: 32px;
 }
@@ -146,16 +146,16 @@ table.itemListTable, table.eventViewTable, table.takeAttendanceTable {
 }
 
 thead tr .tablesorter-header:not(.sorter-false):not(.tablesorter-headerAsc):not(.tablesorter-headerDesc), table.itemListTable thead tr .header, table.takeAttendanceTable thead tr .header, th.tablesorter-headerUnsorted, tr.div-table-row > th.header:not(.headerSortDown):not(.headerSortUp)  {
-    background: url(../images/bg.gif) no-repeat bottom .5em right;
+    background: url(../images/bg.png) no-repeat bottom .5em right;
     cursor: pointer;
     padding-right: 24px;
 }
 
 thead tr .tablesorter-headerAsc, table.itemListTable thead tr .headerSortUp, table.takeAttendanceTable thead tr .headerSortUp, th.headerSortUp {
-    background: url(../images/asc.gif) no-repeat bottom .5em right;
+    background: url(../images/asc.png) no-repeat bottom .5em right;
 }
 thead tr .tablesorter-headerDesc, table.itemListTable thead tr .headerSortDown, table.takeAttendanceTable thead tr .headerSortDown, th.headerSortDown {
-    background: url(../images/desc.gif) no-repeat bottom .5em right;
+    background: url(../images/desc.png) no-repeat bottom .5em right;
 }
 
 table.itemListTable, table.eventViewTable, table.takeAttendanceTable, div.eventFormContainer, form.addEditForm, .addComment h3, td.overviewGradeCol form {
@@ -1088,3 +1088,7 @@ span.yui-skin-sam img {
     font-size: 1.3em;
 }
 
+div#startDateTime span.yui-skin-sam span.yui-calcontainer, div#startDateTime th.calweekdaycell, div#startDateTime td.calcell:not(.oom), div#startDateTime span.yui-skin-sam span.yui-calcontainer a:not(.calnavright):not(.calnavleft), div#startDateTime span.yui-skin-sam span.yui-calcontainer div.title {
+    background: var(--sakai-background-color-2);
+    color: var(--sakai-text-color-2);
+}