Deny access to lib as there are non-PHP files as well (lib/system/api)
Protect log with a .htaccess
Add max-age header for cookies

Closes #1083
Fixed icon names: plus/minus => chevron-right/down

Fixes #1123
Merge branch 'master' of github.com:WoltLab/WCF
Clean up compiled css when cache is cleared
Use short ternary statement
Fix enlarging in ImageViewer
Added fixed width for popovers
Merge branch 'master' of github.com:WoltLab/WCF
Major overhaul of caching system (work in progress)

See #1124
Major overhaul of caching system (work in progress)

See #1124
Major overhaul of caching system (work in progress)

See #1124
Major overhaul of caching system (work in progress)

See #1124
Fixed variable
Fixed install PHP
Imageviewer optimizations
Merge branch 'master' of github.com:WoltLab/WCF
Fixed loop for images
Merge branch 'master' of github.com:WoltLab/WCF