Removes older go version from .travis.yml

Adds 0.5.2, 0.6.0 to CHANGELOG

Merge pull request tomnomnom#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

Adds 0.3.5 to changelog

Adds no-sort flag; minor optimisations