checkcommand to test for strings on https URLs

we were lacking an Icinga checkcommand that had both,
checking https URLs and actual content on them,
either it was missing the -S parameter or one could not
check for content.

needed for something like checking mailman URLs where
https is enforced and we want to check content.

without -S we'd get 404's

to  be used in Ifd3904984bf341 

RT: 7878

Change-Id: I4479e4fc79133f1fc5476256c48cd8d7df63ca90