Add option to configure page size when fetching all entries

[dlitvakb]

When using :all_entries page size is forced to 1000, while this makes fetching everything use less CDA calls, it may be increasing the size of each call to huge amounts, a user reported having a call that returned over 70MB of response.

Therefore we need to add a way of customising the size of each page, while we continue fetching everything, making this use more calls but on smaller and more manageable chunks.