Add docs for vGPU (adapted from blog post)

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Travis, check my stuff!

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Merge pull request #18 from simonjbeaumont/vgpu-docs

Add docs for vGPU (adapted from blog post)
Add alt tag to banner image

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Remove dead external link

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
xenproject.org doesn't use https

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Fix link to xhad repo

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Fixup broken anchor link

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Remove broken external link

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Fixup internal links in VM.start walkthrough

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Fixup external links in VM.start walkthrough

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Add Travis build indicator to README
Merge pull request #20 from simonjbeaumont/htmlproof-fixups

Fix site to pass CI tests (htmlproof)
Use the github-pages preferred gem

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>