change search instrumentation field s/limit/size/
change search instrumentation field s/limit/size/

matches up with how `time` param works. @mtodd you okay with this?

astockwell/ruby-net-ldap,bkeepers/ruby-net-ldap,cloudvolumes/ruby-net-ldap,astockwell/ruby-net-ldap,bkeepers/ruby-net-ldap,cloudvolumes/ruby-net-ldap,javanthropus/ruby-net-ldap,javanthropus/ruby-net-ldap