Internal: upgrade to babel6

Upgrades to babel 6. The major win (aside from some minor
performance gains), is that this module can now be `npm link`ed into a
babel 6 code base.

scripts/build.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+# strict mode http://redsymbol.net/articles/unofficial-bash-strict-mode/
+set -euo pipefail
+IFS=$'\n\t'
+
+
+source "scripts/env.sh"
+
+babel="./node_modules/.bin/babel"
+
+build () {
+  $babel "$SRC_DIR" --out-dir "$OUT_DIR" $@
+}
+
+build $@

scripts/env.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+# strict mode http://redsymbol.net/articles/unofficial-bash-strict-mode/
+set -euo pipefail
+IFS=$'\n\t'
+
+export SRC_DIR="./src"
+export OUT_DIR="./build"

scripts/watch.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+# strict mode http://redsymbol.net/articles/unofficial-bash-strict-mode/
+set -euo pipefail
+IFS=$'\n\t'
+
+./scripts/build.sh --watch