Document the value of md5 for monolingual document, eg. import

this relates to running integrity checker during import localized asset but not pursuing the other update at the moment

common/src/main/java/com/box/l10n/mojito/okapi/steps/AbstractMd5ComputationStep.java

@@ -47,6 +47,9 @@ protected Event handleTextUnit(Event event) {
       if (comments != null && comments.contains(COMMENT_TO_IGNORE)) {
         comments = null;
       }
+      // In the case of an import, for monolingual document, "source" contains the target and this
+      // md5 won't be the md5 that can identify the tm text unit. Only for multilingual document it
+      // would be the case.
       md5 = textUnitUtils.computeTextUnitMD5(name, source, comments);
     }