styles: Inline obsolete order mixin

This CSS property is supported by all of our target browsers by now

see https://caniuse.com/#feat=mdn-css_properties_order

Author: Turbo87

app/styles/_helpers.scss

@@ -64,8 +64,3 @@
     -webkit-flex: $stuff;
     flex: $stuff;
 }
-
-@mixin order($ord) {
-    -webkit-order: $ord;
-    order: $ord;
-}

app/styles/me.scss

@@ -260,9 +260,11 @@
     @media only screen and (max-width: 750px) {
         @include flex-direction(column);
 
-        #my-feed { @include order(0); }
+        #my-feed {
+            order: 0;
+        }
         #my-crate-lists {
-            @include order(1);
+            order: 1;
             margin-right: 0;
         }
         #my-crates, #my-following { margin: 0; }