(flickcurl_photos_getInfo2): Added replacing flickcurl_photos_getInfo

Adds optional 'secret' parameter that was added sometime to the API.

See http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=637746
Make PER-PAGE PAGE docs match code

See http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=635989
Add description of PER-PAGE and PAGE into manpage

See http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=635989
Allow photos.getInfo to take an optional SECRET arg

Call flickcurl_photos_getInfo2() instead of deprecated
flickcurl_photos_getInfo()