#10921
- Changed {{meta_title}} helper to use site meta_title' field
- Changed {{meta_description}} helper to use site 'meta_description' field
- Changed {{og_image}} helper to use site 'og_image' field
- Added site title handling for og/twitter metadata
- Refactored use of 'blog' in variable name in favor of 'site'
- Extended meta_description test suite with 'home' context cases
- Changed {{twitter_image}} helper to use site 'twitter_image' field
- Added ghost_head test for site metadata
- Renamed blog->site in variable names for touched files
refs #10790
- Moved /core/apps into core/frontend
- Moved /core/server/helpers to /core/frontend/helpers along with /core/server/services/themes
- Changed helper location in overrides
- Moved /core/server/services/routing to /core/frontend/services
- Moved /core/server/services/url to /core/frontend/services
- Moved /core/server/data/meta to /core/frontend/meta
- Moved /core/server/services/rss to /core/frontend/services
- Moved /core/server/data/xml to /core/frontend/services
