doc/radosgw: Improve formatting and language in bucket_logging.rst

doc/radosgw: Improve formatting and language in bucket_logging.rst

Trim trailing extra line characters around main title.

Add missing full stops in list items.

Use double backticks for configuration options, data etc.

Linkify reference to REST API.

No hyphen in "regular expression".

Fix section hierarchy by moving "Log Records" up 2 levels and try to
make the section title more consistent with another section title.

Try to improve partial sentences and try to simplify one sentence.

Remove whitespace at otherwise empty line.

Signed-off-by: Ville Ojamo <14869000+bluikko@users.noreply.github.com>