fix malformed pagination urls attempt #2

[gigago]

The previous 'unfix' of pagination urls unfixed my application :-). Since the resulting urls are in fact malformed when base_url contains a scheme id and some browsers don't like this, let's try again to solve this in a different way by appending the filter |replace({':/':'://'}) to each url. Supposedly, this will only affect the scheme part of the url, if any.