First approach of tree view (doesn't work perfectly).

Kai Reinhard

18.31.2018 caf233c0080057c51e2eaad02f8118853ddd205b

 borgbutler-core/src/main/java/de/micromata/borgbutler/cache/ButlerCache.java

@@ -249,12 +249,15 @@
                        if (filter != null && filter.isFinished()) break;
                    }
                }
                if (filter != null) {
                    items = filter.reduce(items);
                }
            }
        }
        if (items == null && forceLoad) {
            log.warn("Repo::archiv with name '" + archive.getBorgIdentifier() + "' not found.");
        }
        return filter.reduce(items);
        return items;
    }

    public List<BorgFilesystemItem> getArchiveContent(File file) {