rename a test to follow naming convention
beef up MockSuiteTests

I thought I had spotted a bug, but it seems I was wrong.  good to have
the additional tests, regardless.
have Travis notify #netlogo on IRC
redo headless.lang tests to use fixture.FunSuite

instead of gross mutable stuff

the added "fixture =>" and "implicit fixture =>" stuff is kind of
noisy, but better than resorting to mutability IMO.

off in headless.model, Josh Cough chose to stash the fixture
in a DynamicVariable to avoid the extra noise. it's something
we could consider.

also rename stuff in headless.lang (sorry part of same commit; I got
all tangled up in git)
tighten up nightly.sh

`all` and `extensions` are about the same now, so no need to do
`extensions` separately anymore. also renumber the phases now
that headless is its own line of development and rapidly drifting
out of sync with 5.0.x and master anyway
refactor/DRY in headless.lang.Fixture
oops, fix regression in headless.lang
make Evaluator.runCompiledCommands/Reporter respect owner.kind

this is a bug or missing feature of long standing, only uncovered now
that I'm about to change headless.lang.Fixture to use these methods
minor code improvement in headless.lang
minor code improvement to headless.lang.Parser

also, sample-scala's tests.txt had an inconsistent test format, which
the improvement caught
code improvement in headless.lang.Fixture

DRY testCommandCompileError out of existence
put headless.lang.ParserTests in its own file
minor code improvement in headless.lang.ParserTests
in headless.lang, rename Procedure -> Declaration

since 'extensions' is allowed too
code improvement in headless.lang.Parser
shuffle code from lang.Parser to lang.Finder
beef up headless.lang.ParserTests
add package-level documentation for headless.lang
update Depend.scala for recent code changes
Merge remote-tracking branch 'origin/headless' into sbt-0.13