the backend code has been added back in, and the build process has been
modified so that no output files are left outside of build/. Admin page
loads and logs in correctly, nothing else functionality-wise yet.
parseDT only uses the magic json.Unmarshal method if theres an error
with the better version. Error came from some times being sent without a
"Z" at the end denoting UTC.
web UI now uses modules, and relies less on bodge to make things work.
Also fixes an issue where invites where "failed to send to xx" appeared
in invite form.