Even though he has very little chance of winning, it might be a good idea for Sanders to keep his name in the race, just in case something happens with Clinton's email scandal. He doesn't need to continue spending money on campaigning, but as long as he's still a candidate, on the off chance that Hillary is forced to drop out for one reason or another, he will be the nominee.
Sanders needs to discontinue his presidential campaign even though Clinton's delegate count continues to rise. He has no chance whatsoever to win the nomination and needs to help Clinton and the party to get her elected. While he made a nice run, it is time for him to leave the race.
It seems that Sanders is shifting over to supporting Clinton and abandoning his campaign, which seems right at this point. He's run a good campaign, but it seems high time for party unity. The Republican party, despite its discontents, has united behind Trump and it's time for Sanders to do the same.
The longer Bernie Sanders continues on with his campaign, the more divided the Democratic party will be in November. Clinton has clearly won the nomination, and the issue of her private email server isn't going to change this. Bernie needs to step away from his campaign, get behind Hillary, and urge his supporters to do the same to avoid losing to Trump in the fall.