=== PartHasContentType

Checks if at least one attachment has a content type header which matches any
element of a comma-separated or space-separated list of content type masks.

Syntax: *match="PartHasContentType=[-d] masks"*

The match is case-insensitive.

Multiple content types name masks can be specified, e.g.: 'application/json,image/png'.

If '*-d*' is coded, some debug info will be logged.
