fix(semver): Ranges can fail with some pre-release numbering

fix(glide): add assert library

fix(*): add support for "DELETING" status

There was a hyphen range bug in semver that prevented constraints
in the form of v2.3.5-20161202202307-sha.e8fc5e5. This would be
parsed incorrectly as a hyphen range and then fail. The bug in
semver was fixed in semver v1.2.2 for this issue.

feat(helm): add support for multiple values files

feat(helm): Add Files.AsSecrets, Files.AsConfig, path functions

Closes #1511

Set Helm deployment to pull IfNotPresent

feat(helm): add newline to fetch --verify output

feat(*): migrate to kubernetes 1.5

feat(ci): add travis configuration

Helm uses fixed tags (e.g. `v2.0.2`) so there should be no need to pull a new image every time.

feat(tiller): add support for resource-policy keep

chore(*): bump go1.7.4

update download links to v2.0.2

You can now specify the `-f` flag multiple times to include multiple
values files. The priority will be given to the last (right-most)
file specified.

Closes #1620