Fix issues causing npm run dev to not work

[jlmitch5]

Just some random fixes to make it possible to npm run dev:

• Fixes an issue where export default was done both on the VisibleTodoList class and its connected/withRouter wrapped instantiation. It just needed to be on the later (and the class didn't need to be exported)
• If you don't have the redux devtools extension installed, the compose call would cause the app to not build as it doesn't play well with undefined. I just followed the example code in the extension's readme to make this work fine (also installed the extension and verified it does work)
• just a quick addition of npm logs to the .gitignore