Add ruby 2.4.0 to .travis.yml
Add ruby 2.4.0 to .travis.yml

breandan/huginn,johnleeming/huginn,huginn/huginn,naiyt/huginn,younata/huginn,Ishfal/huginn,CodeHunter2006/huginn,Ishfal/huginn,naiyt/huginn,gautamkrishnar/huginn,mathias/huginn,johnleeming/huginn,dsander/huginn,breandan/huginn,brianpetro/huginn,virtadpt/huginn,Ishfal/huginn,breandan/huginn,dsander/huginn,brianpetro/huginn,eugenesvk/huginn,johnleeming/huginn,strugee/huginn,CodeHunter2006/huginn,cantino/huginn,huginn/huginn,younata/huginn,mathias/huginn,strugee/huginn,huginn/huginn,naiyt/huginn,cantino/huginn,eugenesvk/huginn,virtadpt/huginn,younata/huginn,dsander/huginn,gautamkrishnar/huginn,brianpetro/huginn,CodeHunter2006/huginn,cantino/huginn,gautamkrishnar/huginn,mathias/huginn,strugee/huginn,eugenesvk/huginn,virtadpt/huginn