ccd_demographic_spell / table completes with warnings

[DocEd]

ccd_demographic_spell is called as part of the anonymisation procedure.

This completes with multiple warnings that don't produce a demographic table correctly. This issue seems to be an upstream component of why the anonymser fails.

There are a lot of interdependencies between ccanonym and cleanEHR and it's worth noting that a lot of cleanEHR is based around directly parsing data from xml - this has already been parsed so some of the functions in play are superfluous and may be producing unexpected outputs as a result. xmlTime2POSIX for example.