Allow duplicate mapping entries

[fscholdei]

Proposed changes

Allow duplicate mapping entries, enrich table labeling

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[eheimbuch]

Well, you fixed the frontend with this. But what about REST? If the frontend merges the entries now i could assume that this happens in general. But if try it out with cURL my last keyword-mapping entry wins.

Example:

curl -X 'PUT' \
  'http://localhost:8081/scm/api/v2/redmine/configuration/scmadmin/a' \
  -H 'accept: */*' \
  -H 'Authorization: Basic c2NtYWRtaW46c2NtYWRtaW4=' \
  -H 'Content-Type: application/json' \
  -d '{
  "url": "",
  "textFormatting": "TEXTILE",
  "autoClose": true,
  "updateIssues": true,
  "username": "",
  "password": "",
  "keywordMapping": {
    "a": "b,b,c",
    "a": "b",
    "a": "b,b,d"
  }
}'