Christopher Boshar of Chelmsford, bottom, with friends and
supporters, from left, Fred Simon, his father Vin Boshar and
John Chemaly. SUN/DAVID H.BROW  They say when life hands you
lemons, you should make lemonade. Christopher Boshar was handed
enough lemons to make a lifetime's supply of lemonade.  And he
still doesn't have a sour bone in his body.  Two years ago,
Boshar was a healthy 25- year- old kid from Chelmsford with a
degree in landscape architecture from UMass Amherst. Then came
the day in July 2011 when he was hanging out with his mother's
family on the family boat at Lake Winnisquam. The boat was
docked at a sandbar, and Boshar went back on board to get a
sandwich. One misstep and he toppled over the side. Next thing
he knew, he was facedown in the water, unable to move.  He
doesn't know how long he was there, but he remembers every
second, especially the feeling that he wasn't long for this
world. "I kind of made peace with the situation," he says.  But
his mother had heard the splash and found Bo