RFR: Allow configuration of version patterns to either include or ignore

[Robin Westberg]

Allow configuring of version patterns that should either be included or ignored when determining which issues are considered when applying the hgupdate-sync label.

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Commit messages:
 - Allow configuration of version patterns to either include or ignore for setting sync label

Changes: https://git.openjdk.java.net/skara/pull/1040/files
 Webrev: https://webrevs.openjdk.java.net/?repo=skara&pr=1040&range=00
  Stats: 158 lines in 5 files changed: 142 ins; 3 del; 13 mod
  Patch: https://git.openjdk.java.net/skara/pull/1040.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/1040/head:pull/1040

PR: https://git.openjdk.java.net/skara/pull/1040