Use of boost::make_shared in parser

For classes lsst::qserv::parser::ModFactory
and lsst::qserv::parser::SelectFactory.
Some replacements couldn't be performed
for next reasons:
* lsst::qserv::parser::ModFactory::LimitH
  ::LimitH(const lsst::qserv::ModFactory&)
  lsst::qserv::parser::ModFactory::OrderByH
  ::OrderByH(const lsst::qserv::ModFactory&)
  lsst::qserv::parser::ModFactory::GroupByH
  ::GroupByH(const lsst::qserv::ModFactory&)
  lsst::qserv::parser::ModFactory::HavingH
  ::HavingH(const lsst::qserv::ModFactory&)
  do not exist.
* lsst::qserv::parser::SelectListFactory
  constructor is private
Use of boost::make_shared in parser: SelectListFactory

For classes:
* lsst::qserv::parser::SelectListFactory
* lsst::qserv::parser::SelectParser
* lsst::qserv::parser::ValueExprFactory
Some replacements couldn't be performed
for next reasons:
* lsst::qserv::parser::SelectListFactory
  ::SelectListH::SelectListH(const
  lsst::qserv::ModFactory::SelectListFactory&)
  lsst::qserv::parser::SelectListFactory
  ::SelectStartH::SelectStartH(const
  lsst::qserv::ModFactory::SelectListFactory&)
  do not exist.
* lsst::qserv::parser::SelectParser
  ::SelectParser(const string&)
  is private