This patch adds an overview page introduced the v2 API concepts via a
worked example. Brought in the entire transitive dep set of protos from
bootstrap.proto, none of these have been cleaned up beyond the minimum
required to have them build under Sphinx.
Also added the ability to link to the underlying proto in messages/enums
from protodoc.py generated RST.
Signed-off-by: Harvey Tuch <htuch@google.com>
As previously pointed out in #9, the empty string is not generally a useful
value in the xDS APIs, so can be be considered equivalent to an unset
field. This is now documented in principles in #28 as well.
Also replace google.protobuf.BytesValue with bytes.