All travellers coming to Britain will be ordered to spend two weeks in quarantine under plans to be announced tomorrow.Prime Minister Boris Johnson is expected to unveil tough new measures aimed at averting a second wave of the coronavirus pandemic.UK airlines say they have been told to prepare for the scheme within weeks.Under the measures, travellers will need to provide authorities with a private address at which they will self-isolate on arrival.Spot checks will be carried out and anyone breaking the rules faces a fine of up to £1,000 or even being deported.But there are fears the move could spell disaster for the aviation and holiday industry, already reeling from the COVID-19 crisis.Any slim hopes of Britons holidaying abroad this