doc/radosgw: Simple fixes and improvements, links improvements

doc/radosgw: Simple fixes and improvements, links improvements

Fix table with a column separator problem in s3/bucketops.rst.

Remove whitespaces at end of lines in s3/bucketops.rst.

Linkify mention of multizone into multisite.rst in bucket_logging.rst.

Separate units from numbers with a space in bucket_logging.rst

Consistency in capitalization and full stop usage in table data in
s3-notification-compatibility.rst s3/bucketops.rst.

Use ref for intra-docs link instead of "external links" feature in
s3/bucketops.rst notifications.rst s3.rst, add a label in start of
s3-notification-compatibility.rst for it. Follow label format that seems
to be in the majority.
Use auto-generated link text that ref provides.
Reflow the text in the cell. Extend table syntax width to accommodate
longer text in cell.

Use ref similarly on links to s3/bucketops.rst. Add a label in it and
use it from bucket_logging.rst and notifications.rst.

Delete unused external link definition in s3/bucketops.rst.

Remove multiple whitespace at the end of lines in notifications.rst
s3-notification-compatibility.rst bucketops.rst.

Change tab characters to spaces in indentation in bucketops.rst

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