By Tommy Wilkes and Simon Jessop LONDON (Reuters) – The biggest shareholder in British housebuilder Countryside Partnerships has urged the board to find a buyer for the group, and to include Inclusive Capital, which has made two bids for the company, in the sales process. U.S.-based activist fund Browning West, which owns 15.3% of Countryside, urged the board to conduct a strategic review of the group, which it said would perform better privately owned or as part of a larger business after board actions led to a “significant destruction of shareholder value”. The letter, dated May 30 and seen …