[#858] update MacOSX database setup instructions
[#858] update MacOSX database setup instructions

PaulVanSchayck/irods,janiheikkinen/irods,janiheikkinen/irods,janiheikkinen/irods,janiheikkinen/irods,janiheikkinen/irods,janiheikkinen/irods,PaulVanSchayck/irods,PaulVanSchayck/irods,PaulVanSchayck/irods,PaulVanSchayck/irods,janiheikkinen/irods,janiheikkinen/irods,PaulVanSchayck/irods,PaulVanSchayck/irods,PaulVanSchayck/irods,janiheikkinen/irods,PaulVanSchayck/irods