Copy-webpack-plugin: [Feature] Provide default `context` option

[cletusw]

Currently, context defaults to compiler.options.context from webpack. However, I'd like all my copy patterns to use ./src as the default context, even though I can't change my webpack context to that for other reasons.

Could we add a fallback to the plugin options? The overall context fallback logic would be:

context property on pattern object -> context property in plugin options -> context property on webpack config

If this sounds okay, I can try to come up with a PR.

[michael-ciniawsky]

The pattern.context isn't sufficient enough for you I guess?

{
   context: 'from/directory', // <= ?
   from: '**/*',
   to: '/absolute/path'
}

Feel free to open a PR if you want to tackle this of course 😛

[cletusw]

Right, all of my patterns are going to repeat the same context, so it'd be nice to just have it once (while allowing overrides, of course)

[cletusw]

@michael-ciniawsky Created #149 to add this option.

[michael-ciniawsky]

@cletusw Any idea on this one #58 :) ?

[cletusw]

@michael-ciniawsky Just added a comment. Not sure what the expected behavior is.