Support including / in webpack alias

[quytang]

The alias config below works ok with webpack but jest-webpack-alias doesn't work properly.

resolve: {
    modules: [path.resolve(__dirname, '..'), 'node_modules'],
    alias: {
        '@app/core': '../apps/core',
        '@app/views': '../apps/components/views'
    }
}

jest-webpack-alias works after I change it to @app-core instead of @app/core, It looks a little tricky.

Could you please help to support slash symbol / in the alias.

Thanks