Update CHANGELOG.md

description of trade fixes that made it into this release
Fixed CITES suspensions search that was not searching on records that don't have a taxon concept or a geo entity set
Changed the timestamp of the download files to account for changes made in the same day but at different times of the day
Added release date to Change log. Added info about extra fix
Merge branch 'hotfix-0.3.2' into develop
Merge branch 'develop' of github.com:unepwcmc/SAPI into develop
Merge branch 'develop' into download_taxon_concepts_list