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

Adds version information to builds; fixes tomnomnom#19

Adds 0.3.2 to changelog

Adds 0.3.1 to changelog