hardly depend on a Page object to make the pager iterable

[docteurklein]

Ease construction of a pager object via Pager::fromResult.

I changed the way the Pager depends on Page. Now you have to pas it a Page instance,
but it eases the end-to-end usage: you only have to use Pager::fromResult($result, $page, $numberPerPage)
and you have a fully iterable pager:

$pager = Pager::fromResult($result, $pageNumber, 10); // $page = 5

var_dump($pager->getPages(2); // as usual: [3, 4, *5*, 6, 7]

foreach ($pager as $item) {
    // iterate on paginated result
}

WDYT?

[beberlei]

@docteurklein It is not backwards compatible, can yo ukeep fromPage as well?

[docteurklein]

@beberlei I'm back from vacation :) I'll try to do that and keep you in touch when it's done.