Build: Update npm deps, fix Sinon npmcopy config

All deps were updated except:
 * jsdom - tests using a Symbol polyfill are hacky and break with newer jsdom;
   we need to re-do them properly first
 * qunitjs - versions 1.19.0 & 1.20.0 introduce race conditions to the tests,
   making the fail randomly

Those two packages will be updated once issues related to them get resolved.

Fixes gh-2877

1 files changed, 3 insertions, 0 deletions

diff --git a/.babelrc b/.babelrc
new file mode 100644
index 000000000..c13c5f627
--- /dev/null
+++ b/.babelrc
@@ -0,0 +1,3 @@
+{
+  "presets": ["es2015"]
+}