Updated the language in describing qcow2 format

... and linked to using SUSE Cloud.
Fixed bnc#829517 for s390 (new network behaviour)
Corrected listing and USER_ID replaceable
Fixed broken URL to API URL, thanks to Tim
Make API URL from last pull request#96 relative
Merge pull request #98 from bear454/master

BNC#827779 Remove /help/create/howto/hyperv.html stub
Add contribution guidelines.
Merge branch 'master' of github.com:susestudio/studio-help

* 'master' of github.com:susestudio/studio-help:
  BNC#827779 Remove /help/create/howto/hyperv.html stub
  Fixed bnc#808381 and added missing types to API documentation
  Small additions for bnc#808377
  Fixed bnc#808377 and added a brief description about qcow2
Mark files as markdown.
Mark up links.
Merge pull request #95 from tomschr/bnc829517

Fixed bnc#829517 for s390 (new network behaviour)
Merge pull request #96 from tomschr/master

Fixed broken URL to API URL, thanks to Tim
Merge pull request #94 from bear454/revised-qcow2-description

Updated the language in describing qcow2 format
Fix link to user page from API help page
Merge pull request #100 from wengel/master

Fix link to user page from API help page
Fix html parser error (bnc#829517)

The parser we use for studio-help could not handle "<USER_ID>" tags. This
commit will remove the angel brackets and present the user id in italic.
a commit to test the github webhook