feat: add upstream and verbose flags to command line interface

feat: add upstream support allowing to chain cache servers if needed
fix: tweaked garbage collection to be better

vfs/fileinfo.go

@@ -12,9 +12,9 @@ type FileInfo struct {
 	ATime time.Time
 }
 
-func NewFileInfo(name string, size int64, modTime time.Time) *FileInfo {
+func NewFileInfo(key string, size int64, modTime time.Time) *FileInfo {
 	return &FileInfo{
-		name:  name,
+		name:  key,
 		size:  size,
 		MTime: modTime,
 		ATime: time.Now(),