Temporarily hide the attachment feature on sandstorm

Our spk currently have an issue with the bundled MongoDB (forked)
version that breaks if some files are inserted in a GridFS collection.

We need to find out a way to upgrade and migrate the bundled database
until we can re-enable the attachment feature.

Note that the feature is unmodified, it's just hidden in the UI.

client/components/cards/cardDetails.jade

@@ -76,7 +76,8 @@ template(name="cardDetailsActionsPopup")
   ul.pop-over-list
     li: a.js-members Edit Members…
     li: a.js-labels Edit Labels…
-    li: a.js-attachments Edit Attachments…
+    unless isSandstorm
+      li: a.js-attachments Edit Attachments…
   hr
   ul.pop-over-list
     li: a.js-move-card Move card

sandstorm-pkgdef.capnp

@@ -22,7 +22,7 @@ const pkgdef :Spk.PackageDefinition = (
     appTitle = (defaultText = "Wekan"),
     # The name of the app as it is displayed to the user.
 
-    appVersion = 3,
+    appVersion = 4,
     # Increment this for every release.
 
     appMarketingVersion = (defaultText = "0.9.0_rc1"),