Javascript style
================

Basics:
- Indent with 2 spaces.
- Keep a maximum line length of 120 characters.
- Prefer "double quotes" for strings/
- Never omit optional semicolons.
- Do not put opening braces or brackets on a new line.
- Call functions without spaces: foo(bar)
- Use 'let' instead of 'var' whenever possible.
- Declare "use strict;".
- Use rocket (=>) syntax for anonymous functions.  If an anonymous function is
  too long, make it a named function.
- Document functions with JSDoc comments (http://usejsdoc.org).

Names:
- Use PascalCase for classes/types, camelCase for variables, functions and
  properties, UPPER_SNAKE_CASE for constants, kebab-case for event names.
- Only capitalize the first letter of an acronym in identifiers.


APIs:
- Prefer 'Promise' to one-shot continuations whenever possible.