Update travis config to use Elixir v0.12.5
Update travis config to use Elixir v0.12.5

manukall/hound,lowks/hound,lowks/hound,jontonsoup/hound,esbullington/hound,esbullington/hound,oivoodoo/hound,oivoodoo/hound,HashNuke/hound,manukall/hound,HashNuke/hound,jontonsoup/hound