def list(user_role)
      response = get_request("/2.0/teams/?role=#{user_role.to_s}")
      return response["values"] unless block_given?
      response["values"].each { |el| yield el }
    end
def list(user_role)
      response = get_request("/2.0/teams/?role=#{user_role.to_s}")
      return response["values"] unless block_given?
      response["values"].each { |el| yield el }
    end
List teams for the authenticated user where the user has the provided role
 Roles are :admin, :contributor, :member

 = Examples
   bitbucket = BitBucket.new :oauth_token => '...', :oauth_secret => '...'
   bitbucket.teams.list(:admin)
   bitbucket.teams.list('member')
   bitbucket.teams.list(:contributor) { |team| ... }