add TestModelDumps

TestModelDumps compares actual to expected JS.
this may help catch regressions in the compiler. but it's also
useful for us to have a corpus of models in JavaScript that
we can look through or grep, for all sorts of reasons
fix resource leak in CompilerService
update 'sbt depend'

to include more Scala standard library stuff we are now using
fix intermittent Travis timeout

by setting LogBuffered to false during slow:test in nightly.sh
Merge pull request #78 from NetLogo/js-dumps

add TestModelDumps