fix(helm): change TILLER_HOST to HELM_HOST

This makes the naming of client-side environment variables consistent.

feat(helm): allow user to specify release name

fix(helm): improve --dry-run for helm delete

fix(helm): print status in helm list output

This prints the status in the long output of helm list,

This makes it possible for the user to specify their own release name
instead of accepting the generated one.

feat(helm): allow overriding values

Right now, some tests need a Tiller instance, and the WIP for that isn't
done yet. So for now, skip this test.

This supports the `-f` flag for overriding values with a specified
TOML file.

fix(helm): allow TILLER_HOME to be used everywhere

fix(style): fixed minor style issues

Offset where the directories and files go from $HELM_HOME to $HELM_HOME/repository

This refactors handling of the TILLER_HOME and HELM_HOME env vars so
that they can be set once and used everywhere. Individual commands no
longer need to handle setting.

ref(helm): fix helm update

chore(helm): fix flag description

fix(helm): allow user to skip namespace creation

This addresses two issues: #699 and #713. It is now possible to skip
creating namespaces. In additional, a trivial bug was fixed that allows
you to create a custom namespace.

fix(helm): change helm repo list to return error when empty

fix(helm): print err if no repositories to update

fix(helm): update main help text

fix(helm): stop processing if lint can't find a chart

fix(helm): print msg and exit when list has no results

This prints an error if 'helm update' finds no repositories to update.

Following other commands, an empty list should return an error.

This exits with an error code if the path resolution fails to find a
chart.

Print no matches found if none are found

fix(cmd): fix init command description