Removed addStatement and removeStatement from StatementsProvider

For details see #71

Author: bekh6ex

src/StatementProvider.js

@@ -34,19 +34,6 @@
 			return this._statementGroupSet;
 		},
 
-		/**
-		 * @param {wikibase.datamodel.Statement} statement
-		 */
-		addStatement: function ( statement ) {
-			this._statementGroupSet.addStatement( statement );
-		},
-
-		/**
-		 * @param {wikibase.datamodel.Statement} statement
-		 */
-		removeStatement: function ( statement ) {
-			this._statementGroupSet.removeStatement( statement );
-		},
 		/**
 		 * @param {string} guid
 		 *