Using a button tag, it's possible for every user to "click" the element.
Besides, we don't need to call the `preventDefault` function, because
buttons with type "button" don't do anything by default.
When we were inserting a row or replacing an existing one (just like we
do when we click the link to select an investment), we were entering a
row containing all columns, and all of them were displayed even if they
had been excluded using the column selector.
This caused the table to move in a strange way, which sometimes made the
investment selection tests fail.
For now we're only adding rules related to spacing and double quotes,
following the same rules we use in Ruby, which are the same rules
CoffeeScript followed when compiling these files.
We're also using the recommended ESLint rules, which will warn us about
many JavaScript common pitfalls, the `strict` rule which enforces using
strict mode, and the `no-console` rule, which will prevent us from
shipping code meant for debugging.
Although it's arguably more common to use the JSON format to define
these rules, I've chosen YAML because it's the format we use in all our
linters.
These statements were automatically added by CoffeeScript.
I'm only removing the obvious cases; there might be more cases where the
`return` statement isn't necessary.
