add ability to rate a missing day

made bgview equatable so it doesn't get redrawn each time a sheet is shown

add more string to localization

fill in missing data on launch ... incase they have bgfetch turned off

Shared/Persistence.swift

@@ -29,6 +29,17 @@ class PersistenceController {
         return PersistenceController.shared.container.viewContext
     }
     
+    public func getEntry(byDate date: Date) -> MoodEntry? {
+        let predicate = NSPredicate(format: "forDate == %@",
+                                    date as NSDate)
+        
+        let fetchRequest = NSFetchRequest<MoodEntry>(entityName: "MoodEntry")
+        fetchRequest.predicate = predicate
+        fetchRequest.sortDescriptors = [NSSortDescriptor(key: "forDate", ascending: true)]
+        let data = try! viewContext.fetch(fetchRequest)
+        return data.first
+    }
+    
     public func add(mood: Mood, forDate date: Date) {
         let newItem = MoodEntry(context: viewContext)
         newItem.timestamp = Date()