Add badges and some code review details

Add to the main README - however note that since we only have PR based
tests right now, if a PR fails, our badges will go red which isn't
really fair to us or the submitter - but we can improve this in #52.

Added a go report card link too - looks like our linting could use some
improvement but we should see how #19 goes (maybe switching out
kubebuilder) before we start following up on all of these.

Also adding some details about code reviews after taking with @tejal29
and @aaron-prindle, specifically leaving the reviews up for a bit longer
than we have been to try to give more folks a chance to comment. Also
added a link to some useful Go coding standards.

CONTRIBUTING.md

@@ -10,7 +10,7 @@ In this file you'll find info on:
 
 * [Principles](#principles)
 * [The pull request process](#pull-request-process)
-* [Commit message requirements](#commit-messages)
+* [Standards](#standards) around [commit messages](#commit-messages) and [code](#coding-standards)
 * [The roadmap and contributions wanted](#roadmap-and-contributions-wanted)
 * [Contacting other contributors](#contact)
 
@@ -52,7 +52,16 @@ Any changes will cause the `/lgtm` label to be removed and it will need to be re
 
 _See also [Knative docs on reviewing](https://github.com/knative/docs/blob/master/community/REVIEWING.md)._
 
-## Commit Messages
+### Review turnaround
+
+Pull requests opened by [maintainers](./OWNERS) should be left open, when possible, for at least a day in order
+to provide other maintainers a chance to review.
+
+## Standards
+
+This section describes the standards we will try to maintain in this repo.
+
+### Commit Messages
 
 All commit messages should follow [these best practices](https://chris.beams.io/posts/git-commit/),
 specifically:
@@ -69,6 +78,12 @@ Not sure what to put? Include:
 * What side effects will this approach have?
 * What future work remains to be done?
 
+### Coding standards
+
+The code in this repo should follow best practices, specifically:
+
+* [Go code review comments](https://github.com/golang/go/wiki/CodeReviewComments)
+
 ## Roadmap and contributions wanted
 
 As of Sept 2018, our roadmap for the next few months is to:

README.md

@@ -1,5 +1,9 @@
 # Pipeline CRD
 
+[![Prow unit test results](https://prow.knative.dev/badge.svg?jobs=pull-knative-build-pipeline-unit-tests)](https://prow.knative.dev/?job=pull-knative-build-pipeline-unit-tests)
+[![Prow build results](https://prow.knative.dev/badge.svg?jobs=pull-knative-build-pipeline-build-tests)](https://prow.knative.dev/?job=pull-knative-build-pipeline-build-tests)
+[![Go Report Card](https://goreportcard.com/badge/knative/serving)](https://goreportcard.com/report/knative/serving)
+
 This repo contains the API definition of the Pipeline CRD and an on cluster implementation of that API.
 The goal of the Pipeline CRD is to provide k8s-style resources that allow the
 declaration of CI/CD-style pipelines, which can be backed by any arbitrary impelmentation.