Fix test/ jslint failures (by not linting tests)

In practice, it's not important to lint tests.  We lint src/
and lib/, which is where we're more prone to make mistakes that
affect real-world situations in subtle ways, and where more
changes are made that ought to be kept in a consistent style.

Tests are a mess anyways, and no one cares.

Makefile

@@ -229,7 +229,7 @@ bench-idle:
 	./node benchmark/idle_clients.js &
 
 jslint:
-	PYTHONPATH=tools/closure_linter/ $(PYTHON) tools/closure_linter/closure_linter/gjslint.py --unix_mode --strict --nojsdoc -r lib/ -r src/ -r test/ --exclude_files lib/punycode.js
+	PYTHONPATH=tools/closure_linter/ $(PYTHON) tools/closure_linter/closure_linter/gjslint.py --unix_mode --strict --nojsdoc -r lib/ -r src/ --exclude_files lib/punycode.js
 
 cpplint:
 	@$(PYTHON) tools/cpplint.py $(wildcard src/*.cc src/*.h src/*.c)