Proposal for datetime formats

@see http://php.net/manual/en/function.date.php

			Full				Medium				Short			Text						Fulltext
date:		d-m-Y				m-Y					d-m				F d, Y						l, F d, Y
time:		H:i:s				H:i					i:s				H:i e						H:i:s e
datetime:	d-m-Y H:i:s			d-m-Y H:i			d-m H:i			F d, Y H:i e				l, F d, Y H:i e
week:		Y-W					W					W-N				W, l						Y-W, l

Example

date:		18-06-1988			06-1988				18-06			June 18, 1988				Saturday, June 18, 1988
time:		17:45:22			17:45				45:22			17:45 GMT					17:45:22 GMT
datetime:	18-06-1988 17:45:22	18-06-1988 17:45	18-06 17:45		June 18, 1988 17:45 GMT		Saturday, June 18, 1988 17:45 GMT
week:		1988-24				24					24-6			24, Saturday				1988-24, Saturday

This is the European date format. During installation, the user should decide which format to use (American or European).