MediaLibrary admin scalability: list_per_page
MediaLibrary admin scalability: list_per_page

The category list and translation overhead is still substantial but this
reduces it by a factor of 4 by dropping the per-page size down to 25.

mjl/feincms,michaelkuty/feincms,nickburlett/feincms,nickburlett/feincms,mjl/feincms,michaelkuty/feincms,joshuajonah/feincms,matthiask/feincms2-content,matthiask/feincms2-content,matthiask/django-content-editor,joshuajonah/feincms,matthiask/django-content-editor,matthiask/django-content-editor,pjdelport/feincms,feincms/feincms,hgrimelid/feincms,nickburlett/feincms,joshuajonah/feincms,joshuajonah/feincms,matthiask/feincms2-content,pjdelport/feincms,michaelkuty/feincms,hgrimelid/feincms,mjl/feincms,feincms/feincms,michaelkuty/feincms,hgrimelid/feincms,nickburlett/feincms,matthiask/django-content-editor,feincms/feincms,pjdelport/feincms