Handle multiple unknown values codes in the same dataset

Related to #29 (closed) #64 (closed) #95 (closed)

• As a fetcher developer
• I want to express multiple values codes for unknown values
• in order to describe totally my dataset

Resources

In: Demandeurs d'emploi - données nationales - CVS - sheet 2 #64 (closed)

Unknown values can be simply blank or set to n.d

How can I define multiple unknown values in my series.json metadata file?

I would prefer to have a list for storing unknown values