Merge: code: cleanup some docunits

They where detected since #1332 is merged

Pull-Request: #1508
Reviewed-by: Alexis Laferrière <alexis.laf@xymus.net>
Reviewed-by: Romain Chanoir <chanoir.romain@courrier.uqam.ca>

diff --cc lib/standard/file.nit
Simple merge

diff --cc lib/standard/text/ropes.nit
Simple merge