[package] add missing css sources

sources/dhtmlxgantt.css

@@ -1,5 +1,5 @@
 /*
-This software is allowed to use under GPL or you need to obtain Commercial or Enterise License 
+This software is allowed to use under GPL or you need to obtain Commercial or Enterprise License
  to use it in non-GPL project. Please contact [email protected] for details
 */
 .gridHoverStyle {
@@ -69,6 +69,9 @@ This software is allowed to use under GPL or you need to obtain Commercial or En
 .gantt_task_line.gantt_project .gantt_task_progress {
   background-color: #46ad51;
 }
+/*
+	milestone
+*/
 /*
 	lightbox
 */
@@ -564,6 +567,7 @@ div.dhx_modal_cover {
 .gantt_task_content {
   font-size: 12px;
   color: #ffffff;
+  width: 100%;
   position: absolute;
   white-space: nowrap;
   text-align: center;
@@ -775,6 +779,29 @@ div.dhx_modal_cover {
 .gantt_task_line.gantt_project.gantt_selected {
   box-shadow: 0 0 5px #46ad51;
 }
+.gantt_task_line.gantt_milestone {
+  visibility: hidden;
+  background-color: #d33daf;
+  border: 0px solid #61164f;
+  box-sizing: content-box;
+  -moz-box-sizing: content-box;
+}
+.gantt_task_line.gantt_milestone div {
+  visibility: visible;
+}
+.gantt_task_line.gantt_milestone .gantt_task_content {
+  background: inherit;
+  border: inherit;
+  border-width: 1px;
+  border-radius: inherit;
+  box-sizing: border-box;
+  -moz-box-sizing: border-box;
+  -webkit-transform: rotate(45deg);
+  -moz-transform: rotate(45deg);
+  -ms-transform: rotate(45deg);
+  -o-transform: rotate(45deg);
+  transform: rotate(45deg);
+}
 .dhx_unselectable,
 .dhx_unselectable div {
   -webkit-user-select: none;