[proposal][next-version] Merge branches into one

[kybarg]

There are many branches in this project each dedicated to some usage case. I suggest to merge all branches into one, but let user to specify install options depending on which one will get installation of redux, fullstack, universal-redux etc.
Other variant is to have basic pack and extend with yeoman generator.

[diegohaz]

Having those branches can make our work a little harder, but the gain is enormous.

• It helps us to better handle and track bugs;

• If something breaks on universal-redux, the other branches will be fine;

• If we need to upgrade some library, like react-router v4 for example, we don't need to worry about whether it will work with redux and SSR or not. We can just upgrade it on master and leave the others with v3 until it has proper support;

• Even if we focus on the generator-arc (and that's the plan), let people to git clone the boilerplate easily is desirable since one can take advantage of git history (to keep local in sync);

• If one already has a project and want to know how to implement redux, for example, comparing branches can help them:

  

[diegohaz]

But I'll probably look for a maintainer for fullstack soon since I'm not using that branch on any project and therefore can't guarantee further improvements.