Clarify cloning from home page.
Fixed bnc#790930: Online help: Description of login
Add docu for kiwi import via API, 656096
Update 800_api/920_v2/250_overlay_files.md

Typo Fix: change -> changed
Update 400_use/500_xen-image.md

Aligned appearance to what we use on other pages:
- Italic to emphasise certain words
- Bold 'Note'
Updated PR
Merge pull request #49 from bgeuken/kiwi_import_via_api

Add docu for kiwi import via API, 656096
Update 400_use/500_xen-image.md
Merge pull request #51 from bgeuken/patch-3

Update 400_use/500_xen-image.md
Merge pull request #50 from bgeuken/patch-2

Update 800_api/920_v2/250_overlay_files.md
Merge pull request #52 from bgeuken/patch-4

Update 400_use/500_xen-image.md for bnc#793621
Update 400_use/500_xen-image.md

Small update after Thomas review
Merge pull request #53 from bgeuken/patch-5

Update 400_use/500_xen-image.md
Merge pull request #48 from tomschr/bnc790930

Fixed bnc#790930: Online help: Description of login
Merge branch 'master' into onsite

* master:
  Update 400_use/500_xen-image.md
  Update 400_use/500_xen-image.md
  Updated PR
  Update 400_use/500_xen-image.md
  Update 800_api/920_v2/250_overlay_files.md
  Add docu for kiwi import via API, 656096
  Fixed bnc#790930: Online help: Description of login
  Clarify cloning from home page.