[IMP] etree-ify default view generations
[IMP] etree-ify default view generations

* Search already used etree internally, remove serialization to string
* form and tree were easy to convert
* pull down fvg's parsing (etree.fromstring) into calendar generator before converting it
gisce/openobject-server,splbio/openobject-server,vnc-biz/openerp-server,gisce/openobject-server,splbio/openobject-server,ovnicraft/openerp-server,MarkusTeufelberger/openobject-server,ovnicraft/openerp-server,splbio/openobject-server,MarkusTeufelberger/openobject-server,MarkusTeufelberger/openobject-server,vnc-biz/openerp-server,gisce/openobject-server