Stock display (#379)

* Display stock quantity more prominently

* Cleanup search widget

* Update for stock_detail widget

* More tweaks

* Change bottom bar icon

* Display boolean parameters appropriately

* Adds ability to edit part parameters

* Bump icon size a bit

* Improvements to filter options

- Allow filtering by "option" type
- To start with, filter stock by status code

* Remove debug message

* Remove getTriState method

- No longer needed
- Remove associated unit tests

* Adjust filters based on server API version

* Muted colors

lib/widget/part_detail.dart

@@ -228,20 +228,6 @@ class _PartDisplayState extends RefreshableState<PartDetailWidget> {
     });
   }
 
-
-  /*
-   * Toggle the "star" status of this paricular part
-   */
-  Future <void> _toggleStar(BuildContext context) async {
-
-    if (InvenTreePart().canView) {
-      showLoadingOverlay(context);
-      await part.update(values: {"starred": "${!part.starred}"});
-      hideLoadingOverlay();
-      refresh(context);
-    }
-  }
-
   void _editPartDialog(BuildContext context) {
 
     part.editForm(
@@ -259,13 +245,11 @@ class _PartDisplayState extends RefreshableState<PartDetailWidget> {
         child: ListTile(
           title: Text("${part.fullname}"),
           subtitle: Text("${part.description}"),
-          trailing: IconButton(
-            icon: FaIcon(part.starred ? FontAwesomeIcons.solidStar : FontAwesomeIcons.star,
-              color: part.starred ? Colors.yellowAccent : null,
-            ),
-            onPressed: () {
-              _toggleStar(context);
-            },
+          trailing: Text(
+            part.stockString(),
+            style: TextStyle(
+              fontSize: 20,
+            )
           ),
           leading: GestureDetector(
             child: api.getImage(part.thumbnail),