Add a checksum function to the template engine

fix(semver): range handling includes prerelease when it should not

fix(helm): improve --set parser

fix(helm): fix windows support with port forward connection in setupConnection

This fixes the port forward connection using helm on windows by assigning explicitely 'localhost' to 'TillerHost' in 'setupConnection'. Otherwise, the connection between the helm client with the Tiller server deployed on Kubernetes will not work.

A bug in the semver package caused prereleases to be included in
version ranges by default. Prereleases, per the spec, are not
expected to be API compatible with the releases themselves.

The semver package now ignores prereleases when evaluating
constraints when the constraint does not contain a prerelease. If
the constraint contains a prerelease they are evaluated.

chore(*): remove glide hacks that are no longer required

This replaces the old set parser with a brand new one. This also changes
the internal algorithm from duplicating YAML to merging YAML, which
might solve a problem one user reported in chat, but which was never
captured in an issue.

Closes #1540
Closes #1556

feat(helm): support 'helm create --starter=mypack'

This adds support for packs, pre-configured chart patterns that can be
used to quickly create a custom layout for your new chart.

fix(helm): don't pass nil-opt to ReleaseContent

feat(kube): add schema validation

Adds validation against the swagger schema.

Example error:
Error: release telling-wildebeest failed: error validating "": error
validating data: expected type int, for field
spec.template.spec.containers[0].ports[0].containerPort, got string

Current error:
unable to decode "": [pos 177]: json: expect char '"' but got char 'n'"'

fix(requirements): accept semver constraints for the versions in the requirements.yaml

fix(tiller): allow release name to be up to 53 chars

fix(kube): fix incomplete patches generated on update

docs(yaml_techniques): add YAML techniques document

This raises the limit from 14 to 53 chars based on the Kubernetes 1.4
name limit.

Closes #1528

This documents YAML and provides information about how Helm and
Kubernetes interpret the YAML.

fix(tiller): return yaml parsing errors

feat(tiller): add source file to log entries

feat(gometalinter): Move to versioned releases

fix(helm): helm create will not overwrite existing files

feat(charts): Move bucket to domain from path

fix(tiller): show failed YAML

use openssl instead of shasum

fix(helm): respect dryRun opt in DeleteRelease

shasum is not on many platforms (like centos), use openssl instead.

gometalinter has moved to versioned releases. The latest of the v1
major versioned releases can be retrieved through pkg.in. This
change moves gometalinter use to the latest v1 release.

Downloading of charts and helm itself happened over http. This
change moves to use https as that is available with valid certs.

closes: #1519