Merge pull request #19 from AdrienGiboire/gh-pages

Add PPCG as Partner
updated brochure link
valid sponsor brochure link
Merge pull request #20 from zaiste/sponsor-link

valid sponsor brochure link
Merge branch 'gh-pages' of github.com:rupyconf/13.rupy.eu into gh-pages
github partner
Merge pull request #21 from albanlv/gh-pages

Github partner
Add registration link