The database files have been doubled in size compared to the previous files being used.
For this reason the database files are now gzip compressed, which required using
`GZIPInputStream` when loading database files.
* `rename` processor, renamed `to` to `target_field`
* `date` processor, renamed `match_field` to `field` and renamed `match_formats` to `formats`
* `geoip` processor, renamed `source_field` to `field` and renamed `fields` to `properties`
* `attachment` processor, renamed `source_field` to `field` and renamed `fields` to `properties`
Closes#17835
- move ingest plugin docs to core reference docs
- move geoip processor docs to plugins/ingest-geoip.asciidoc
- add missing options tables for some processors
- add description of pipeline definition
- add description of processor definitions including common parameters
like "tag" and "on_failure"
Christoph Wurm
Martijn van Groningen
DeDe Morton
Tal Levy