Transpile @polymer but not all of node_modules

[leegee]

polymer-skeleton/webpack.config.js

Line 134 in 0da8b09

// exclude: /(node_modules)/,

Since we can use a regexp, we can use its less commonly-used negative lookahead operator:

/node_modules\/(?!(@?polymer))/

[LasaleFamine]

Hi @leegee, thank you for reporting this one, would you like to open a PR for this?