Fix issue #28: cannot read property 'pathname' of undefined

[mrmuhammadali]

I was getting errors while configuring the plugin, I opened an issue so I thought why not I solve it myself. So here are the steps I did:

1. Created flatCombineReducers utility which merges reducers without need of a key like combineReducers does.
2. Created a routerReducer which is required by connected-router-redux
3. Merged router reducer and root reducer, i.e. routerReducer and reducer
4. Replaced store reducer with the merged reducer.

[CLAassistant]

All committers have signed the CLA.

[mrmuhammadali]

@KevinGrandon Can you look into this PR?

[KevinGrandon]

Thanks for the PR. We really want to get this landed, but can't quite yet due to the following:

• This is likely an error due to a newer version of the connected router.
• We can't upgrade the connected router due to requiring React 15 support.

We are working on a roadmap for React 15, and will revisit this as soon as we have React 15 deprecation planned.