copy install/step4.php from una-orig branch

Revert "more safety install script"

This reverts commit 933e2eb0bf89f6682b684893d8a124fdd6b3392d.
epgrec una 20140427
Merge branch 'una-orig' into asuha

Conflicts:
	DBRecord.class.php
	Keyword.class.php
	recomplete.php
	recordedTable.php
	sendstream.php