SHINDIG-1378: Caja removes unknown attributes in os:PeopleSelector

The os:PeopleSelector tag definition generates the following attributes in the select tag which are stripped by Caja:
x-var
x-max
x-onselect

The fix is to move this data into the constructor.

Messages from Caja:
stdin:stdin:62: elect" onchange="os_PeopleSelector_onchange(this)" x-max="2" x-onselect=""
x-var
                                                                                         
WARNING: stdin:stdin:62+123 - 128: removing unknown attribute x-var on select
stdin:stdin:62: ="peopleSelect" onchange="os_PeopleSelector_onchange(this)" x-max="2" x-onselect

WARNING: stdin:stdin:62+109 - 119: removing unknown attribute x-onselect on select
stdin:stdin:62: "multiple" name="peopleSelect" onchange="os_PeopleSelector_onchange(this)"
x-max
                                                                                         
WARNING: stdin:stdin:62+99 - 104: removing unknown attribute x-max on select

Caja Issue: http://code.google.com/p/google-caja/issues/detail?id=933
JIRA: https://issues.apache.org/jira/browse/SHINDIG-1378

[chirag, 2010-07-16 20:32:02]

Fix issues with quoting parameters found by Felix

[Jasvir, 2010-07-16 21:01:55]

LGTM