move pkg cmd/helm/strvals to pkg/strvals

This is another useful package outside of cmd/helm.

Fixing pkg->cmd call by moving helmpath under /pkg

Including Helm Chart Publisher in related.md

fix(docs): Updates hook documentation for `--wait` flag

The behavior of how the `--wait` flag interacts with the hook lifecycle
was not documented. This adds clarification on the lifecycle behavior
with the `--wait` flag.

fixing typo

Fix link to charts.md file

feat(helm): add support for required properties

Adds the `required` function in enginge.go to support required
properties in values.yml. When a chart developer wishes to specify
intent in requiring a value, they can use this function to declare
an error message that gets returned when chart rendering fails
when a required value is not present in values.yml.

Closes #1580

docs(related): add "Using Helm to Deploy to Kubernetes"

docs(README): update downloads to 2.2.2.

docs(chart_best_practices): create best practices guide

Clarify inheritance behavior for global variables

fix checksum example

This adds a basic Chart Best Practices guide.

Closes #1993

$.Template.basePath already contains "templates/"

Add .Template.BasePath to template system

install: Return more user-friendly response on eexists

Fix helm dep list reporting wrong status

docs(related): Add link to helm-diff plugin

Link to the Helm Chart repository from the Helm project

Add toToml template function

When downloader package moved to under /pkg, helmpath functions got called still from it, while it is under /cmd. This commit fixes the issue by moving helmpath after the downloader to have only cmd->pkg and pkg->pkg calls.

Version matching is used for checking status of subcharts.
closes: #2056

The current README makes no mention of the Chart repository or where to find it. You have to Google to find it or stumble upon it. It was frustrating to come to the Helm project and not easily be able to find where the chart repository was - even though I knew it existed. This patch will make that easier for others.

fix(tiller): Fixes `--wait` panic on upgrade

Most newcomers hit helm's 'feature' there deleted instalations are not really deleted.
Use-case
# helm install  --name gitlab-ce-1 ./stable/gitlab-ce
# helm delete gitlab-ce-1
# helm list
# helm install  --name gitlab-ce-1 ./stable/gitlab-ce
Error: a release named "gitlab-ce-1" already exists

There is a lot duplicated bugs in bugzilla which simply explains that packages
should be deleted with --pure flag. But such bugs appeared again and again
because this behavior is not obvious.

Let's help user to figure out what happens ASAP.

local path repo verbose - issue #2020