Added multi-option search along.

Added auto hiding of categories in search unless selected.
Added field allowing to choose whether category auto-hidden

Fixes #353

assets/migrations/0013_auto_20191016_1446.py

@@ -0,0 +1,22 @@
+# Generated by Django 2.0.13 on 2019-10-16 13:46
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('assets', '0012_auto_20191014_0012'),
+    ]
+
+    operations = [
+        migrations.AlterModelOptions(
+            name='asset',
+            options={'ordering': ['asset_id'], 'permissions': (('asset_finance', 'Can see financial data for assets'),)},
+        ),
+        migrations.AddField(
+            model_name='assetstatus',
+            name='should_show',
+            field=models.BooleanField(default=True, help_text='Should this be shown by default in the asset list.'),
+        ),
+    ]