Test(CI) setup code coverage

Also moves ava config to package.json

scripts/test.sh

@@ -0,0 +1,14 @@
+#!/bin/bash
+# strict mode http://redsymbol.net/articles/unofficial-bash-strict-mode/
+set -euo pipefail
+IFS=$'\n\t'
+
+nyc=./node_modules/.bin/nyc
+ava=./node_modules/.bin/ava
+
+if [ ! -z ${CI:-} ]; then
+  $nyc $ava --tap=${CI-false} | tap-xunit > $CIRCLE_TEST_REPORTS/ava/ava.xml
+else
+  $nyc $ava
+fi
+