Add node to testing suite. Add plugin validation note in changelog.

Author: nhunzaker

CHANGELOG.md

@@ -2,6 +2,12 @@
 
 ## 9.2.0 (not released)
 
+### Noticeable changes
+
+- Plugins will now validate that their `register` property is a
+  function. If this property is not present, it will skip this
+  validation and continue to the next plugin.
+
 ### Internal changes
 
 - Internalized `is-generator` package to reduce dependencies and cut

Makefile

@@ -56,8 +56,10 @@ audit:
 	@gzip -c $(DIST)/microcosm.build.js | wc -c
 
 test:
-	NODE_ENV=test karma start --single-run
-	NODE_ENV=test make test-fast
+	@ echo "Testing browsers..."
+	@ NODE_ENV=test karma start --single-run
+	@ echo "Testing node..."
+	@NODE_ENV=test make test-fast
 
 test-fast: $(shell find {src,examples} -name '*-test.js')
 	@ mocha -R dot --compilers js:babel/register $^