eslint: standardize on single quoted strings
eslint: forbid unused function arguments

We added an exception to this way back with the idea that this would
make callbacks nicer since they could all have the same signature.
However, this also meant that we did not detect when arguments became
unused due to refactoring. As an example, ObjectCtrl had two unused
injected arguments.
package: update eslint to 0.9.2 by upgrading grunt-eslint

This is the newest version and allows us to use new rules.
eslint: enable comma-style

This rule was introduced in eslint 0.9.0 and is off by default. No
change needed since we already used this style.
eslint: require function declarations where possible

Instead of defining a local function as

  var func = function () { ... };

we now require a function declaration:

  function func() { ... };

This is the style already in use.
eslint: forbid padding inside blocks
eslint: remove some unnecessary quotes on object properties

These were found by the quote-props rule. We cannot enable it fully
since it conflicts with the camelcase rule:

  {'foo_bar': 123}

is not accepted by quote-props, but

  {foo_bar: 123}

is also not accepted by camelcase.
eslint: standardize on space after "function" keyword

The old code was written line

  var func = function() { ... }

whereas newer code was written like

  var func = function () { ... }

I like the newer style better since it is more consisten with the
spaceing in a named function:

  var func = function func() { ... }

There were also more cases with space than without.
eslint: standardize on space before "{"
eslint: forbid space inside parentheses

We were already using this style, so no further changes needed.
Merge pull request #174 from mgeisler/style-cleanups

Style cleanups