Merge branch 'master'
Merge branch 'master/master'
Couchbase site provider. Added CustomerErrorProvider and UrlRedirectProvider.
UrlRedirects Provider & CustomErrors Provider
regen uuid when import site.
Added ABTest providers.
Fixed the ABProvider bug.
Fixed a title bug. In url redirect import page. The title should be "import url redirects", but not "import custom error"
1,Sub sites export.
2,Site null bug.
File management issue.
Fixed ABPageSetting export issue.
SiteProvider ABTestProviders
Merge pull request #1 from Kooboo/master

Merge
Device detecting when resolve a site. #215
#219
SiteProvider ABTestProviders
Fixed the site null bug.
Merge pull request #221 from Tsingbo-Kooboo/SiteProvider

EntityFramework Site provider
Merge pull request #222 from ZhiGuang/master

CouchBase Providers
StyleEditor bug fixed