A tag is required to reuse Elasticsearch breaking changes in the Stack
Guide. To display properly, the breaking changes must use external
links rather than xrefs.
This PR correctly places those tags for reuse. It also replaces
several xrefs with external links for reuse.
We already deprecated and removed the camel-case versions of the nGram and edgeNGram
filters a while ago and we should do the same with the nGram and edgeNGram tokenizers.
This PR deprecates the use of these names in favour of ngram and edge_ngram in 7
and disallows usage in new indices starting with 8.
Closes#50561
The removal of the "nGram" and "edgeNGram" token filter was filed in a new
migrate_8_0/mappings.asciidoc document but it should better be in an
analysis.asciidoc section and file.