Add skills page

Initial stage
Remove concat and cssmin
Update uglify config
Update js
Add skills-matrix module
Add d3 library
Create skills matrix page and add basic d3.js
Experiment with d3.js
Merge branch 'master' into feature/add-skills-page
Update skills function to use json data
Merge branch 'master' into feature/add-skills-page

Conflicts:
	_layouts/default.html
Add easy pie chart of skills matrix amongst other design tweaks
Update subheading
Finalise skills page
Tweak colours of each skill group
Add frameworks to skills page
Add ui-list styles
Merge pull request #2 from ashliewebb/feature/add-skills-page

Feature/add skills page