Replace usage of controls label with our custom label

This prevents copy pasting a bunch of parameters that we set by default

resources/qml/Account/GeneralOperations.qml

@@ -4,7 +4,7 @@
 import QtQuick 2.10
 import QtQuick.Controls 2.3
 
-import UM 1.4 as UM
+import UM 1.5 as UM
 import Cura 1.1 as Cura
 
 Column
@@ -12,14 +12,12 @@ Column
     spacing: UM.Theme.getSize("default_margin").width
     padding: UM.Theme.getSize("default_margin").width
 
-    Label
+    UM.Label
     {
         id: title
         anchors.horizontalCenter: parent.horizontalCenter
-        renderType: Text.NativeRendering
         text: catalog.i18nc("@label",  "Sign in to the Ultimaker platform")
         font: UM.Theme.getFont("large_bold")
-        color: UM.Theme.getColor("text")
     }
 
     Image
@@ -33,16 +31,13 @@ Column
         verticalAlignment: Image.AlignVCenter
     }
 
-    Label
+    UM.Label
     {
         id: generalInformationPoints
         anchors.horizontalCenter: parent.horizontalCenter
         horizontalAlignment: Text.AlignLeft
-        renderType: Text.NativeRendering
         text: catalog.i18nc("@text", "- Add material profiles and plug-ins from the Marketplace\n- Back-up and sync your material profiles and plug-ins\n- Share ideas and get help from 48,000+ users in the Ultimaker community")
         lineHeight: 1.4
-        font: UM.Theme.getFont("default")
-        color: UM.Theme.getColor("text")
     }
 
     Cura.PrimaryButton