Implement getFileInfo to retrieve meta data

getFileInfo returns a record containing meta data about the given file,
such as permissions, last modification time and time. We'll use this
action to fill a neat status bar.

package.yaml

@@ -11,9 +11,9 @@ extra-source-files:
 
 dependencies:
   - base >= 4.13 && < 5
+  - time
+  - directory
 #  - bytestring
-#  - time
-#  - directory
 
 ghc-options:
   - -Wall