MANCHESTER, England (Reuters) - British Prime Minister Theresa May said the government would do everything it could to help restore Northern Ireland s power-sharing government, adding that Brexit would not herald the return of a hard border between the British province and Ireland.  I believe very firmly that the decisions for Northern Ireland are best made in Northern Ireland in that devolved administration. So we want to see that executive up and running,  May said.   We have been very clear, and the European Union agrees with us, that there should no physical infrastructure on the border,  she said.  It is important ... that we don t return to the hard border of the past.  