Set coffee logger filename with authenticated user's id
Allow user to open different files
wip - save display name when saving a user's coffee log file
Cut down coffee logger API

-remove unused functionality
-remove it's responsibility for knowing about files
-inject file abstraction as dependency

We only want the coffee logger to be about getting log data, and
updating log data. If it doesn't need to know about *how* the file
context switches (e.g. filenames and display names), just *when* the
file context switches, then we can really simplify this layer, and
clarify the division of responsibility in the app.

We also cut out "reviews", since they aren't being used yet. There's
also no reason to use an object to store records. An array works just as
well, and we don't have to track the latest key value manually.
remove filename/displayName dichotomy, let user specify filenames

The need for display names goes away when users can specify friendly
names for their files, rather than naming files by user id.

In spite of this simplification, we create a file abstraction to sit
between the datastore and the coffee log, which handles file context
switching - opening existing files and creating new ones.
Clean up file selector view

-Update text and prompt for new file button.
-Open existing file if user specifies an existing file name.
-Show selected file when user creates a new file.
Push file-loaded-indicator logic into coffee log view

rather than cluttering the app initialization
style file selector
remove example spec
Clean up rewrite of coffee logger

Rewrite tests, clean up naming, and remove dead code.
Overhaul coffee log view

Update fields to be specific to the methods used in the office.

Let barista be determined once upon instantiation of the view, so that
the user doesn't have to enter it.

Remove date logic from view (todo: make this part of coffee logger).

Fix tests to reflect new view API.
Have coffee logger attach date information to added records
Add field defaults and units to coffee log view
Update app entrypoint to use new coffee log view API

specifically, initialize it with the barista's name
Render dates more nicely
Remove json gcs index parser

Since we stopped trying to have separate real and display names for
files, we no longer need a special index parser--we can assume that the
index method returns a list of filenames.
Clean up file selector view

Add tests, remove unused stuff.

To aid with testing, inject prompt as a dependency.

Directly invoking a passed reference to window.prompt is illegal, so
wrap it in an anonymous passthrough function.
Fix intervals in app initializer