Remove type-level analyzer, index_analyzer, search_analyzer

[clintongormley]

Type level default analyzers are problematic. While the index analyzer can always be applied, the search analyzer is only applied if the type name is prepended to the field (see #3102).

With the changes planned in #8870, fields will be mapped in the same way across all types in an index, so it no longer makes sense to have type-level default analyzers. Instead, index-level default analyzers will apply to all fields (ie analyzers named default, default_search, or default_index).

Relates to #8870