[Doc] Quality issues in plugin docs (incorrect asciidoc formatting, missing content)

Quality issues in plugin docs (continued from #6693) Reference: Support Matrix

Global:

[ ] Style of the description varies from plugin to plugin. Would be nice to make the descriptions for consistent in style (at least for the plugins that we maintain).

Input plugins:

[x] plugins-inputs-redis.
- [x] Options are out of order.
- [x] ssl missing from options table
[x] plugins-inputs-snmp. Options are out of order.
[ ] VPR (various): beats. Deprecation text. (See https://github.com/elastic/docs/pull/1005)
[ ] VPR (various): tcp. MD
[ ] In plugins-inputs-cloudwatch:
- [x] Only 1 of the 3 examples is properly formatted as JSON.
- [x] "Configuration Example" heading is formatted incorrectly
- [ ] "Configuration Example" should be sentence case and plural
- [ ] List under filter option needs returns to render correct. Correct typos.
[ ] Edit plugins-inputs-file
[ ] In plugins-inputs-gelf, the example is not correctly formatted as xml.
[ ] In plugins-inputs-gemfire:
- [ ] Note is not formatted (needs to say NOTE: instead of Note: to get the correct formatting).
- [ ] Example under cache_xml_file is not correctly formatted as XML.
[ ] ⭐️ In plugins-inputs-http_poller:
- [ ] Description of validate_after_inactivity option contains weird formatting and # sign.
- [ ] This topic needs an edit. Contains typos, missing periods, etc.
- [ ] See https://github.com/logstash-plugins/logstash-input-http_poller/issues/99
[ ] In plugins-inputs-imap, lots of options are missing descriptions.
[x] In plugins-inputs-lumberjack, URL is formatted in markup style, not asciidoc.

Output Plugins:

[ ] plugins-outputs-elastic_app_search-url. Incorrect formatting on Note.
[ ] logstash-output-elasticsearch. Comma splice on proxy description
[ ] VPR (various): circonus. Formatting for code samples
[ ] VPR (various): librato. Formatting for code samples
[ ] VPR (various): riak. Formatting for code samples
[ ] VPR (various): riemann. Formatting for code samples
[ ] VPR (various): grok. Formatting for code samples
[ ] VPR (various): s3. MD
[ ] plugins-outputs-boundary needs an edit. What do people have against periods anyhow? Some of the descriptions are hard to follow.
[ ] plugins-outputs-csv needs an edit.
[ ] plugins-outputs-datadog:
- [ ] Needs an edit.
- [x] Fixed: The intro is in the wrong place, so it's not being pulled into the topic.
- [ ] Descriptions of the available options aren't very useful.
[ ] In plugins-outputs-elasticsearch, add a note about migration from doc to _doc
[ ] plugins-outputs-graphtastic needs an edit. The writing seems almost confessional.
[ ] In plugins-outputs-kafka
- [ ] Fixed: text in table overruns navigation.
- [x] Formatting of options described under acks could be better.
[ ] outputs-nagios_nsca.html), the example is not correctly formatted (gets broken into 2 examples).**
[ ] plugins-outputs-redmine needs an edit. Cringe-worthy typos.

Filter Plugins:

[ ] geoip might have an incorrect link. Research further. {ref}/geo-point.html[Elasticsearch Geo_point datatype]
[ ] VPR (various): MD
[ ] In filters-elapsed, correct default coding for periodic_flush. See discussion in #36
[ ] In filters-elapsed, correct default coding for periodic_flush. See discussion in #36
[ ] In plugins-filters-drop, some of the examples don't use the correct asciidoc example formatting type for the data that's shown.
[ ] In plugins-filters-mutate, add an example to illustrate nesting
[ ] In plugins-filters-elapsed, some of the examples don't use the correct asciidoc example formatting type for the data that's shown.
[ ] In plugins-filters-environment, some of the examples don't use the correct asciidoc example formatting type for the data that's shown.
[ ] In plugins-filters-metricize, the examples in the intro don't use the correct example formatting.
[ ] **In plugins-filters-throttle. Has been removed from CI.
- [ ] some of the example formatting is messed up with the example being broken into a mixture of example and text.**

Codec Plugins:

[ ] In plugins-codecs-cef, the example under the delimiter option needs to be formatted correctly
[ ] plugins-codecs-dots doesn't really contain any doc content. Needs an example at least.
[ ] plugins-codecs-edn doesn't really contain any doc content. Added description, but still needs an example.
[ ] plugins-codecs-edn_lines doesn't really contain any doc content. Added description, but still needs an example
[ ] plugins-codecs-msgpack doesn't really contain any doc content. Added description, but still needs an example.
[ ] In plugins-codecs-nmap, the list of event types should be formatted as a list.
[ ] In plugins-codecs-protobuf, link is formatted incorrectly and bullet list under the include_path option needs formatting.

Integrations:

Meta:

[ ] In filters-elapsed, correct default coding for periodic_flush. See discussion in #36. NOTE: From CS: "I just looked at elastic/logstash#6693 and note that this also impacts the metrics, aggregate, multilines and throttle filters (per my quick search ^^)"

elastic / logstash