Renamed: logging.md -> devel/logging.m
Renamed: access.md -> design/access.md
Renamed: identifiers.md -> design/identifiers.md
Renamed: labels.md -> design/labels.md
Renamed: namespaces.md -> design/namespaces.md
Renamed: security.md -> design/security.md
Renamed: networking.md -> design/networking.md
Added abbreviated user user-focused document in place of most moved docs.
Added docs/README.md explains how docs are organized.
Added short, user-oriented documentation on labels
Added a glossary.
Fixed up some links.
This commit addresses issue #1571, which requests that all internal
Kubernetes links are swapped to relative ones to better facilitate
browsing of documentation on local forks, not to mention make the
documentation have less needless boilerplate.