Oil prices inched up Tuesday, as traders weighed production outages in the US and tensions in the Middle East and Europe against rising crude supply in Libya and Norway. Brent crude futures were up 30 cents, or 0.4%, to $80.36 a barrel at 1618 GMT. US WTI crude futures gained 46 cents, or 0.6%, to $75.22 a barrel. In the ME, tensions rose the morning after US and British forces carried out a