Update .travis.yml
Update .travis.yml

Add ./bin to the $PATH so `/usr/bin/env lfe` can work and disable
builds for R14-16 for now. Use R16B03-1 (commented out).

jjl/lfe,oubiwann/lfe,oubiwann/lfe,jjl/lfe,arpunk/lfe,yurrriq/lfe,bsmr-erlang/lfe,arpunk/lfe,yurrriq/lfe,bsmr-erlang/lfe