[QuickStatements] Remove "identical statements" restriction

[Jonáš Dyba]

In QS:Help it is stated that "Existing statements with an exact match (property and value) will not be added again". I can see why this was added, but now it poses a problem when trying to add elo rating statements. Sometimes the rating doesnt change for a player over time and when I try to add a rating with identical value as a different month, then QS "merges" those two statements or doesnt add it at all. Is there a way to force QS to add those statements?