Adds -v/--values option; updates release script

Removes older go version from .travis.yml

Removes older go version from .travis.yml

Adds 0.5.2, 0.6.0 to CHANGELOG

Merge pull request #31 from SimePel/master

Reduces nesting and inverts validURL condition

Updates changelog ahead of 0.5.1

Adds 0.5.0 to CHANGELOG

Adds 0.4.0 to changelog

Adds 0.3.7 to changelog

Adds 0.3.6 to changelog