add design/ dir and doc template (#1636)

Signed-off-by: Steve Kriss <krisss@vmware.com>

design/_template.md

@@ -0,0 +1,48 @@
+# Design proposal template (replace with your proposal's title)
+
+Status: {Draft,Accepted,Declined}
+
+One to two sentences that describes the goal of this proposal.
+The reader should be able to tell by the title, and the opening paragraph, if this document is relevant to them.
+
+_Note_: The preferred style for design documents is one sentence per line.
+*Do not wrap lines*.
+This aids in review of the document as changes to a line are not obscured by the reflowing those changes caused and has a side effect of avoiding debate about one or two space after a period.
+
+## Goals
+
+- A short list of things which will be accomplished by implementing this proposal.
+- Two things is ok.
+- Three is pushing it.
+- More than three goals suggests that the proposal's scope is too large.
+
+## Non Goals
+
+- A short list of items which are:
+- a. out of scope
+- b. follow on items which are deliberately excluded from this proposal.
+
+## Background
+
+One to two paragraphs of exposition to set the context for this proposal.
+
+## High-Level Design
+
+One to two paragraphs that describe the high level changes that will be made to implement this proposal.
+
+## Detailed Design
+
+A detailed design describing how the changes to the product should be made.
+
+The names of types, fields, interfaces, and methods should be agreed on here, not debated in code review.
+The same applies to changes in CRDs, YAML examples, and so on.
+
+Ideally the changes should be made in sequence so that the work required to implement this design can be done incrementally, possibly in parallel.
+
+## Alternatives Considered
+
+If there are alternative high level or detailed designs that were not pursued they should be called out here with a brief explanation of why they were not pursued.
+
+## Security Considerations
+
+If this proposal has an impact to the security of the product, its users, or data stored or transmitted via the product, they must be addressed here.