docs: surface dictionary_path-related settings

[yaauie]

Makes refresh_interval and refresh_behaviour more discoverable in the context of dictionary_path

[jsvd]

From the initial request for clarification we also need to make clear that the contents are entirely stored in memory. A suggestion:

Suggested change

	* See also: <<plugins-{type}s-{plugin}-refresh_interval>> and <<plugins-{type}s-{plugin}-refresh_behaviour>>
	The full path of the external dictionary file. The format of the table should be
	a standard YAML, JSON, or CSV.
	* See also: <<plugins-{type}s-{plugin}-refresh_interval>> and <<plugins-{type}s-{plugin}-refresh_behaviour>>
	The full path of the external dictionary file.
	The dictionary is read into memory to allow fast lookups, so make sure the JVM Heap is sized to fit its entire content.
	The format of the table should be a standard YAML, JSON, or CSV.