Thus enable getpageinfo_p API to return something in a reasonable amount
of time on resources over MegaBytes size range.
Support added first with the generic XML parser, for other formats
regular crawler limits apply as usual.
For faster processing (measured about 2 times faster on many real-world
examples) and more advanced detection (previous algorithm detected only
URLs separated from the rest of the text by a space character).
add "datetime" property of <time> tag to scrapers startdate list.
Datetime is parsed as iso8601 (xml) date, html5 allows partial as well
as duration (not handled by this)
luccioman