Fix equations in NHERD update

Add hinge loss function as in the original paper for safety
crc32 is not needed in jubatus_core itself
Remove unnecessary std::max
Merge pull request #47 from hido/fix-816

Fix equations in classifier/NHERD update
Merge pull request #50 from jubatus/refactor/jubatus_core_doesnt_use_crc32

jubatus core doesnt use crc32
bump version
Merge branch 'release/0.0.3' into develop