admin part, opencart documentation link was fixed
changed the directory image/data to image/catalog
Merge pull request #714 from hkulekci/patch-fix

admin part, opencart documentation link was fixed
more admin update done
Merge branch 'master' of https://github.com/opencart/opencart

Conflicts:
	upload/admin/view/template/common/header.tpl
updated header
added an ad tracking system so store owners can gage which ad placements generate sales.
header has been updated to match the new design
updated the path for loading the affiliate model