RFR: translate: better helptext for --map

[Erik Helin]

Hi all,

please review this small patch that updates the helptext for `git translate --map`.

Thanks,
Erik

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Commit messages:
 - translate: better helptext for --map

Changes: https://git.openjdk.java.net/skara/pull/781/files
 Webrev: https://webrevs.openjdk.java.net/?repo=skara&pr=781&range=00
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/skara/pull/781.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/781/head:pull/781

PR: https://git.openjdk.java.net/skara/pull/781