fix(helm): respect kubeconfig default namespace

fix(tiller): delete all revisions with --purge

closes: #1395

fix(helm): make 'helm repo index' generate the right index

fixes: #1396

This prevents the index command from recursing through directories.
Behind the scenes, it swaps out the repository logic for the index file
logic.

Closes #1328

fix(1357): print help text if revision is not specified

feat(helm): `--no-update` flag for `helm repo add`

fix(helm): show failed releases by default

doc(rollback): add docs for pre/post rollback hooks

docs(provenance): describe signature authority

fix(tiller): fix wording for a few errors

fix(tiller): fix nil pointers in error messages

This changes the wording of a log and an error message to make it
clearer what is happening.

There were a few places where error messages were accessing properties
of objects that were nil because of the error.

Closes #1374

For 'helm list', this now shows both deployed and failed releases by
default.

Closes #1387

fix(kube): find current resource by name and kind

fix(*): statically link cross builds

fix(helm): return correct version on dep up

docs(*): refresh docs

closes: #1362

fix(1333): cannot delete release in failed state

There was an extra return statement in a helper that was causing
the download manager to get a false positive on a release version.

Closes #1383

This resolves #1210. Update will find current resource
by name and kind for comparison purposes.

This refreshes docs, as discussed in #719, and adds a few new sections
to the docs.

Closes #719

Fix/tiller helm flags

docs(helm): Fix broken link to glide project

fix(linter): add engine.FuncMap so linter can use real function list

chore(docs): fix nginx example templates

Closes #1072

This adds a function engine.FuncMap that returns a function mapping that
better represents the functions passed to a template. The linting logic
is reconfigured to use this function instead of the sprig.FuncMap
function.

Closes #1366

fix(lint): validateNoMissingValues template regex