Update .travis.yaml to use irteus/test/irteus-demo.l

Update .travis.yaml to use irteus/test/irteus-demo.l to reduce code for do-until-key overwriting.
In terms of moving test codes discussed in the PR[1],
first of all, I tried this commit because I'd like to check 
amount of standard-output and execution time which have influence on travis testing.

[1] https://github.com/euslisp/jskeus/pull/80