Fix up chart linting, add docs and lint script (#146)

This updates the Helm linting system with the following changes:

- Import lintconf.yaml with small change to comment distance in order to
match existing values.yaml standards
- Update Chart.yaml and values.yaml in each chart to pass linting
standards
- Maintainers added to each chart from OWNERS + CODEOWNERS, the linter
requires GitHub usernames so argo-events maintainer names were converted
- README updated with documentation around chart standards and testing
- A local shell script added for running lint tests locally

scripts/lint.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+set -eux
+
+SRCROOT="$(cd "$(dirname "$0")/.." && pwd)"
+
+for dir in $(find $SRCROOT/charts -mindepth 1 -maxdepth 1 -type d);
+do
+ name=$(basename $dir)
+ echo "Running Helm linting for $name"
+ docker run \
+    -v "$SRCROOT:/workdir" \
+    gcr.io/kubernetes-charts-ci/test-image:v3.0.1 \
+    ct \
+    lint \
+    --config .circleci/chart-testing.yaml \
+    --lint-conf .circleci/lintconf.yaml \
+    --charts "/workdir/charts/${name}"
+done