BUGFIX Versioned_Version->relField() so fields can be used in GridField etc

Copied from DataObject, since we can't use the $fallback opion in this case
(will try to retrieve from wrong class)
BUGFIX: fix for broken layout in insert media dialog - Trac #8232
BUG Undefined `$allowed_actions` overrides parent definitions, stricter handling of $allowed_actions on Extension

Controller (and subclasses) failed to enforce $allowed_action restrictions
on parent classes if a child class didn't have it explicitly defined.

Controllers which are extended with $allowed_actions (through an Extension)
now deny access to methods defined on the controller, unless this class also has them in its own
$allowed_actions definition.
Improved docs on $allowed_actions

Added section to "Controllers" and "Form" topics,
added $allowed_actions definitions to all controller examples
BUGFIX Keep Member.PasswordEncryption setting on empty passwords

This will prevent empty passwords to set the encryption to 'none',
which in turn will store any subsequent password changes in cleartext.
Reproduceable e.g. with ConfirmedPasswordField and setCanBeEmpty(true).
Add ContentController->handleWidget() to $allowed_actions

Required by recent $allowed_actions security fix
Updated changelog
BUG setBody on SS_HTTPRequest is a function

When settingt he cached body on the RESTfulService_Response, the setBody should be a function call, not a variable assignment
Note about RestfulService SSL verification in upgrading guide
ENHANCEMENT: fixed styling bug with the text in the file upload drop area and moved allowed extensions up a tad
MINOR:forgot to add the fix to the insert media upload field - styles from files section were breaking it.
BUG Undefined var

Getting the curl error.
BUG UnsavedRelationList aren't checked

When saveInto is called on ListboxField and CheckboxsetField,
UnsavedRelationList should be an acceptable relationship type. This is
leading to relations not being saved on initial creation of Member
objects
Fixed issue with cms help toggles not functioning correctly
No longer caching the target element to be toggled
FIX handleAction methods should be protected now
BUG Transaction stub methods for better cross 2.x and 3.x compat

The transactionStart() naming is 3.x, and used by some modules
which are otherwise still 2.x compatible.

Specifically, this was added to avoid branching the payment module
into separate 2.x and 3.x compatible branches.
API Make Object::config use late static binding

Can now be used in instance scope, like:
  $this->config()->db
and in static scope, like:
  Page::config()->db
Cache the merged version of any Config value in an in-mem LRU cache
Extract statics via code analysis rather than introspection