refactor suggestions + improvements

[goldylucks]

Some ideas to consider (or merge :) ) from glancing over the code. Hope this helps, feel free to ask or comment! :)

• add support for vscode eslint
• handle multiple classes with classnames
• validate bitcoin address
• fix support email text and use constant instead of hardcoded
• convert routes to constants instead hardcoded
• use getters to simplify code
• abstract some reidrect logic to functions
• move styles to bottom of file (demonstration of putting the "important" stuff above the fold / as higher as possible in the file)
• simplify rendering (especially in Welcome)
• export reducers from reducers/reducers.js instead of reducers/index.js - this is a discoverability trick to reduce the amount of index.js files open in the browser, so it's clearer at first glance which file you are working one
• improve readme