Update ruby sass for libsass about fe-skeleton

[anthonyhastings]

I burned about two hours on this looking into the whole build chain of gulp-sass which depends on node-sass which depends on libsass.

Findings are that I can't clone node-sass using node 0.11.15 and npm 2.6.0 due to the following error:
Can not download file from https://raw.githubusercontent.com/sass/node-sass-binaries/v2.0.1/linux-x64-node-0.11/binding.node

Also, external sourcemaps seem to be still very much incomplete:
sass/node-sass#731

Without being able to set sourceRoot of the Source Maps to point at the true location of our source files, they'll still not work.

[anthonyhastings]

Awaiting NodeSource for Ubuntu to release 0.12:
nodesource/distributions#63

[anthonyhastings]

Test Case 1

html,
body {
    margin: 0;
    padding: 0;
    height: 100%;
}

.m-example-module {
    color: green;
    text-align: center;

    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    width: 100%;
}

Results

• ruby sass average compile after 6 tests: 399ms
• libsass average compile after 6 tests: 78ms

libsass is over 5x faster.

Test Case 2

This test case uses the avengers web application and the CSS source files located within it.

Results

• ruby sass average compile after 6 tests: 517ms
• libsass average compile after 6 tests: 126ms

libsass is over 4x faster.