Update npm and ruby dependencies

- ~~Optimise SVGs with latest version of SVGO~~ (SVGO 0.4.5 seems unpredictable)
- Introduce new scss-lint rule: UnnecessaryParentReference (and removed unnecessary `&` nested selectors)

## Update Sass from 3.3.7 to 3.3.14

### 3.3.14 (1 August 2014)

* Improved edge-case parsing of special-syntax functions like `calc()` and
  `expression()`.

* Fixed a bug when using `--update` with absolute paths on Windows.

### 3.3.13 (31 July 2014)

* Fixed a bug on ruby 2.0 where watching several folders was broken.
  Work around for a [bug in listen](https://github.com/guard/listen/issues/243).

### 3.3.12 (29 July 2014)

* The Sass::Compiler class has a number of new minor features to support
  Compass's compilation needs:

  * The template_deleted event of the Sass Compiler class now runs before the
    side-effect events.
  * The Sass Compiler class can now be used to clean output files.
  * The Sass Compiler class now exposes an updating_stylesheets callback
    that runs before stylesheets are mass-updated.
  * The Sass Compiler class now exposes a the compilation_starting callback
    that runs before an individual stylesheet is compiled.
  * The Sass Compiler class now runs the updated_stylesheets callback
    after stylesheets are mass-updated.
  * The Sass Compiler can now be made to skip the initial update
    when watching.

### 3.3.11 (25 July 2014)

* `str-slice()` now correctly returns an empty string when `$end-at` is 0.

### 3.3.10 (11 July 2014)

* Properly encode URLs in sourcemaps.

### 3.3.9 (27 June 2014)

* Defining a function named "and", "or", or "not" is now an error at
  definition-time. This isn't considered a backwards-incompatible change because
  although these functions could be defined previously, they could never be
  successfully invoked.

* Fix deprecation warnings for using `File.exists?` on recent Ruby versions.

* Fix a bug where `@extend` within `@at-root` could crash the compiler.

* Gracefully handle the inability to change cache files' permissions.

### 3.3.8 (20 May 2014)

* When a use of `@at-root` doesn't add any new rules, it will no longer split
  its containing block in two ([issue 1239][]).

* Fix a `sass-convert` bug where rules would occasionally be folded together
  incorrectly when converting from CSS to Sass.

* Fix error messages for dynamically-generated `@media` queries with empty
  queries.

[issue 1239]: https://github.com/nex3/sass/issues/1239

## ~~Update SVGO from 0.4.4 to 0.4.5~~

Version 0.4.5 of SVGO was generating new files at every optimisation. Meaning at every sprite generation there would have been a new SVG file (also: somewhat badly optimised).


![ ](http://media.giphy.com/media/iXMxeh4m1YS52/giphy.gif)