Merge pull request #458 from guytarded/filesystem

Filesystem
Added more info about how you can upgrade your module.
Merge branch 'filesystem' of github.com:forkcms/forkcms into filesystem
Filesystem: Search module (backend)
Updated the upgrade-guide
Filesystem: Settings module (backend)
Merge remote-tracking branch 'upstream/filesystem' into filesystem
fix typo
Filesystem: Tags module (backend)
Filesystem: Users module (backend)
Filesystem: Installer step 7
Filesystem: applied filesystem component to frontend/core
self not found, needed to be SpoonFilter
Filesystem: applied to frontend modules
Filesystem: swap SpoonFileException with IOException
Merge pull request #461 from guytarded/filesystem

Filesystem
Replaced SpoonFileException with IOException
Updated upgrade-guide
Use the filesystem-service in the API
Use the filesystem-service in BackendLanguage