It was a light moment at the Connecticut Technology Council board meeting in October when Bruce Carlson, the group’s CEO, quipped the fastest way to sell a company with favorable terms was to join the council’s board. It was that kind of year in 2017 for the tech sector in a state economy otherwise starved for good news. At least six big sales closed for Connecticut tech businesses, led by $1.5 billion for Datto in Norwalk. Five had an executive on the tech council’s 48-member board. More to the point, all six will stay put with the goal of growing in their home state. Datto, the business data protection and connectivity firm, sold Oct. 26 to Vista Equity Partners in a deal that included a merger with another firm, Autotask.