Update npm and ruby dependencies

[kaelig]

• 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.

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.

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).

[rich-nguyen]

👍

[ironsidevsquincy]

That's one detailed PR

[kaelig]

I have reverted the npm dependency update.

SVGO was unpredictable, generating a new (larger) SVG at each compilation. Kept only Ruby updates.