Correct docblock for BP_XProfile_Field_Type_URL::display_filter()

git-svn-id: https://buddypress.svn.wordpress.org/trunk@8671 cdf35c40-ae34-48e0-9cc9-0c9da1808c22
Introduce BP_XProfile_Field_Type::pre_validate_filter(), and use in URL field type

The pre_validate_filter() method allows field types to intercept field values,
before they are run through the is_valid() validation routine, and optionally
modify them.

BP_XProfile_Field_Type_URL uses this filter to silently add the 'http://'
protocol to submitted values before run through the validation regex (which
requires the protocol). The result is a smoother UX, as users are not required
to enter the protocol in order to have their field value saved.

To make it possible for protocol-less values to be submitted on the profile
edit form, the 'type' attribute of the URL field was changed from 'url' to
'text' (with a 'url' inputtype). With 'type=url', modern browsers require a
fully-qualified URL before allowing the form to be submitted.

Fixes #5501

git-svn-id: https://buddypress.svn.wordpress.org/trunk@8672 cdf35c40-ae34-48e0-9cc9-0c9da1808c22