Chart.js version and usage with angular-chart.js

Hello,

I am trying to use the LinearGauge extension with the angular-chart.js wrapper for Angular.js.
So far I am not really successful as I get the following error message:
`Uncaught TypeError: Cannot read property 'extend' of undefined Chart.LinearGauge.js:313`
The line 313 reads:
`Chart.Type.extend({
name: "Linear",
defaults: defaultConfig,
....
`

I am wondering if it could be caused by LinearGauge not being designed for Chart.js version 2x.