Fix habit creation

app/src/main/java/org/isoron/uhabits/models/sqlite/SQLiteHabitList.java

@@ -84,6 +84,9 @@ public class SQLiteHabitList extends HabitList
         if (id == null) id = record.save();
         else record.save(id);
 
+        if(id < 0)
+            throw new IllegalArgumentException("habit could not be saved");
+
         habit.setId(id);
         cache.put(id, habit);
     }

app/src/main/java/org/isoron/uhabits/models/sqlite/records/HabitRecord.java

@@ -147,6 +147,7 @@ public class HabitRecord extends Model implements SQLiteRecord
         Frequency freq = model.getFrequency();
         this.freqNum = freq.getNumerator();
         this.freqDen = freq.getDenominator();
+        this.reminderDays = 0;
 
         if (model.hasReminder())
         {