created the %clearfix silent class
created $grid related variables
Created variable aliases
* Resolved #10 - added $sass-silent-classes variable as well as it's aliases
* Removed aliases comments from _variables.scss this instead will be provided in documentation.
created all needed SASS mixins for grid
created _grid.scss
Fixed some small issues with _sass-helpers.scss
* Resolve #13: created a sticky-footer class
* fixed an issue with container margins.
* created testing environment
Merge branch 'feature/grid' into develop

* Resolve #1: created custom grid for framework
* Updated CHANGELOG.md
* Updated README.md

* feature/grid:
  * fixed an issue with container margins. * created testing environment
  * Resolve #13: created a sticky-footer class
  * Fixed some small issues with _sass-helpers.scss
  * created _grid.scss
  * created all needed SASS mixins for grid
  * Resolved #10 - added $sass-silent-classes variable as well as it's aliases * Removed aliases comments from _variables.scss this instead will be provided in documentation.
  * Created variable aliases
  * Created $grid related variables
  * Created the %clearfix silent class