Simplify exposing raw C helpers in _helperlib, by exposing a dict containing all references, instead of individual get_* functions.
Merge branch 'master' of github.com:numba/numba into c_helpers_dict
Merge pull request #533 from pitrou/c_helpers_dict

Simplify exposing raw C helpers in _helperlib, by exposing a dict contai...
Merge branch 'master' of github.com:numba/numba into trunc_int_return_width