Opposition nominates Imamoglu as Turkey's presidential candidate / Turkish president due in Islamabad today / Turkish president arrives today / Turkish government establishes Family Institute, Population Policies Board / Turkish opposition leader rules out new constitution talks / Turkish government resubmits 'agents of influence' bill to parliament / Turkish presidential advisor believes Erdogan should serve another term / Russia, Turkey need better coordination between legislatures -- Turkish parliament speaker / Prime minister holds bilateral meeting with Turkish president at UNGA 79 / Turkish president vows to 'purge' military graduates who took a pro-secular oath