Add rescan option to overflow dropdown (#1119)

* Make scan options optional
* Add scene rescan
* Add image rescan
* Add gallery rescan
* Add changelog

pkg/utils/boolean.go

@@ -7,3 +7,8 @@ func Btoi(b bool) int {
 	}
 	return 0
 }
+
+// IsTrue returns true if the bool pointer is not nil and true.
+func IsTrue(b *bool) bool {
+	return b != nil && *b
+}