Add new methods isDev() and isDevServer()

[Kocal]

Hi,

This PR adds two new methods isDev() and isDevServer() aside the already existing isProduction() method.

On a project at work, we should configure webpack-encore only when we are running the dev-server.
There is the property runtimeConfig.useDevServer but we don't have access to runtimeConfig in our webpack.config.js.

I know we can do this:

const config = Encore.getWebpackConfig();

if (config.devServer) {
  // ....
}

but it means that we can't use webpack-encore methods:

if (Encore.isDevServer()) {
  Encore
    .setPublicPath('http://app.vm:8080/build/')
    .setManifestKeyPrefix('build/')
}

Also I tried to add some tests but I didn't find tests for isProduction() :(

Thanks!

[Kocal]

Hum, test failures are unrelated right? 🤔

[Lyrkan]

Hi @Kocal,

Thanks for the PR, I only have a small comment about it.

And the failing test is, indeed, unrelated (it's caused by some hashes that were not updated after a recent PR).

[Kocal]

Removed === true from the check :)

[weaverryan]

Makes good sense - thank you Hugo!