Show loader name together with deprecation warning

[AlexKvazos]

Currently deprecation warnings are logged without the name of the loader that caused the issue.

The only way of debugging this is to try each loader one by one to see which one is shooting that warning.

[jhnns]

Put process.traceDeprecation = true inside your webpack.config.js and node will output a stack trace. Alternatively, you can also start your process with node --trace-deprecation node_modules/.bin/webpack

This is node's default way of handling deprecations. The usability is not good, but we've brought that already up.

[ryanve]

Is process meant to be key in the webpack config object or the node built-in process?

[scholtzm]

@ryanve I couldn't get the process flag to work, had to use the CLI switch at the end.

[ryanve]

Thanks @scholtzm