fix js file inclusion

in v8, js/css files are no longer included from __openerp__.py, but by updating
the qweb template
fix call to close_callforbids

the id of the purchase requisition is no longer in active_ids but in tender_id,
passed in the context.
add missing check for default is None
fix flake8 warning
Merge remote-tracking branch 'remotes/lep/8.0-add-purchase_requisition_extended' into 8.0-test_PRs