If there is a selection in the query then only that part is Executed or explained.

Replaced QTextEdit with QPLainTextEdit as it is more efficient and CAN do syntax highlighting.

mainwindow.h

@@ -64,6 +64,7 @@ private:
 
 	void query_ready(std::shared_ptr<Pgsql::Result> res);
 	void explain_ready(std::shared_ptr<ExplainRoot> explain);
+	std::string getCommand() const;
 private slots:
 
 	void startConnect();