Reinvent boost string algorithms #47
Description
https://github.com/rmartinho/nonius/blob/devel/include/nonius/detail/cpptempl.h uses boost::lexical_cast, boost::trim_copy_if, boost::trim_copy, boost::is_space, boost::split, and boost::starts_with. If the boost dependencies are to go away, these need to be replaced with non-boost equivalents.