Support for dl-protect.com
Fix for dl-protect.com

Infinite redirecting occured when a file had a password but no captcha.
Support for mirrorupload.net
Support for firedrive.com
Merge remote-tracking branch 'devnoname120/dl-protect.com' into v5

close #409
dl-protect.com

Move to new category.
Add API to count items in collection.
Fix dispatch algorithm.
Add API to access collection.
dl-protect.com

Improve control flow.
Merge remote-tracking branch 'devnoname120/mirrorupload.net' into v5

close #411
mirrorupload.net

Move to new category.
Merge remote-tracking branch 'devnoname120/firedrive.com' into v5

close #417
firedrive.com

Move to new category.