WIP: file system: import

src/main/java/org/caosdb/server/entity/Entity.java

...main/java/org/caosdb/server/filesystem/FSODescriptor.java

...va/org/caosdb/server/filesystem/FileStorageInterface.java

src/main/java/org/caosdb/server/filesystem/FileSystem.java

...n/java/org/caosdb/server/filesystem/LocalFileStorage.java

.../java/org/caosdb/server/filesystem/SharedFileStorage.java

...osdb/server/filesystem/VirtualFSODescriptorInterface.java

...aosdb/server/filesystem/consistency/ConsistencyCheck.java

src/main/java/org/caosdb/server/jobs/FilesJob.java

...ava/org/caosdb/server/jobs/core/CheckTargetPathValid.java

src/main/java/org/caosdb/server/utils/ServerMessages.java