include option to delete records from GDC in wis2box

[maaikelimper]

@tomkralidis it has been noted that the GDC contains old records due to the recreation of datasets between wis2box-release updates

For example for Brazil, the GDC has:

urn:wmo:md:br-inmet:
urn:wmo:md:br-inmet:alerts
urn:wmo:md:br-inmet:cap
urn:wmo:md:br-inmet:daycli
urn:wmo:md:br-inmet:surface-based-observations.synop
urn:wmo:md:br-inmet:surface-based-observations.temp
urn:wmo:md:br-inmet:synop
urn:wmo:md:br-inmet:synop-aut
urn:wmo:md:br-inmet:synop-man
urn:wmo:md:br-inmet:upper-air

While the Brazil WIS2 Node currently actually only has these records:

urn:wmo:md:br-inmet:alerts
urn:wmo:md:br-inmet:daycli
urn:wmo:md:br-inmet:synop
urn:wmo:md:br-inmet:synop-man
urn:wmo:md:br-inmet:upper-air

@golfvert asked:
Unless I am missing something, I think it is not (really) a software issue but some incorrect practice from the user side.
Nevertheless, one way to fix it is to send a deletion message for the different metadata_id.
Is that something doable in the software ?

Can we include a "deletion" module ?

Regards,
Rémy

[maaikelimper]

@tomkralidis should this still be part of sprint-018 ?