Support both http and https Flickr URLs

Flickr have switched to https links by default for flickr.com/photos/ and flic.kr/p/. The http versions are still being used and supported by Flickr. Both http and https work for secure.flickr.com/photos/.

This patch supports both http and https for all Flickr URLs

 * Tested on Symbian with a Nokia 808.
 * Confirmed Harmattan builds.
 * Also includes PR #25 (block user).