BNS and NS glossary does not match actual usage

The user guide glossary defines BNS as a system comprised of two neutron stars and BHNS as a system of one neutron star and one black hole. However, the alert categories of BNS and BHNS instead used for two sub 3 solar mass objects, as described in the inference section. It is likely that the maximum mass of neutron stars is well below 3 solar masses, so many objects in this category must actually be black holes. As a concrete example with discussion in LVK publication, GW190814 was considered most likely a BBH. In contrast , the HasNS categorization uses EOS marginalization to actually asses whether a NS may present based on mass. This is a different definition than used for BNS/BHNS and can for example lead to a BHNS event where HasNS is negligible. The difference in the two uses of "NS" (either below 3 solar masses, or potentially a NS mass) needs to be clearly conveyed in the guide.

@shaon.ghosh, @deep.chatterjee, @sushant.sharma-chaudhary, @andrew.toivonen, would you please take a look at this?