Remove whitespace from LeftAndMain_Menu
Trigger delete confirmation popup when deleting a GridFieldDetailForm record
Merge pull request #1158 from halkyon/deleteaction

Trigger delete confirmation popup when deleting a GridFieldDetailForm re...
NEW Don't load CMS preview iframe if not visible (fixes #8247)
Fixed DatetimeField formatting (single row, smaller field)

Also removed the arbitrary right-floating of fields within a fieldgroup
API Removed 'BadLoginURL' session var from MemberLoginForm

It was never set in core, and is generally undocumented,
hence just unnecessarily increases the security surface
of this sensitive class.
DataObject on*() callbacks now consistently invoke on subclasses as well

Before this was only possible for some specific ones, like onBeforeWrite.
This excludes any callbacks with augment*() or update*() naming,
since these are assumed to be on extension only, with a corresponding
base method available on the class itself (e.g. "updateCMSFields()"
vs "getCMSFields()").
BUGFIX: fix for broken layout in insert media dialog - Trac #8232
Merge branch '3.1' of git://github.com/silverstripe/sapphire into open8232