logging: Log Format Example and value type

[fabiog1901]

Fabio Ghirardello (fabiog1901) commented:

Adding example after every log format

On page https://www.cockroachlabs.com/docs/stable/log-formats.html we list the various log formats, however, we've only 1 example after crdb-v2. It would be helpful to show what a format looks like by putting an example after every log format.

In my case, I didn't know that timestamp for json-fluentd-compact would have been in the format of epoch time, instead of YYYY-MM-DD HH:MM:SS.SSSSSS.

Jira Issue: DOC-1477

[thtruo]

FYI @taroface I've added this to https://cockroachlabs.atlassian.net/browse/DO-63