Initial review

[nbradbury]

• gradle.properties-example refers to simperiumKey as "your-app-key" but it's called "API key" on the web site
• The link to https://simperium.com/tutorials/simpletodo-android is a 404 (but it's a nice 404)
• When the signin screen appears, the "Already have an account? Sign In" label is obscured by the keyboard
• Each of the classes under com.simperium.simpletodo would benefit from code analysis (I see unused declarations, unused imports, and a number of "declaration access can be weaker" warnings)
• This seems like an unfortunate kludge to have in a sample app
• It would be helpful if each of the bucket listeners here had a comment explaining their purpose
• In general the app would benefit from more commenting - there are a lot of unexplained methods for a sample project.
• Related to the above, explaining why refreshTodos must be run on the main thread would be helpful (that sort of thing could trip up a lot of devs)
• ACTION_ID is a constant in the fragment but is hard-coded in the layout. Can an integers.xml value be used here instead?