RFR: 1538: Allow regex patterns in fixversions and altfixversions in the notifier

[Erik Joelsson]

This patch adds support for regex patterns when specifying fixVersions and altFixVersions in the IssueNotifier. For fixVersions, the branch name can now be a regex pattern and for the altFixVersions, both the branch name as well as the version strings in the array can all be regex patterns. Having this flexibility will enable us to construct much more static configurations for certain repositories, that don't need manual updating each time we fork or branch a new release.

-------------

Commit messages:
 - SKARA-1538

Changes: https://git.openjdk.org/skara/pull/1414/files
 Webrev: https://webrevs.openjdk.org/?repo=skara&pr=1414&range=00
  Issue: https://bugs.openjdk.org/browse/SKARA-1538
  Stats: 153 lines in 6 files changed: 113 ins; 8 del; 32 mod
  Patch: https://git.openjdk.org/skara/pull/1414.diff
  Fetch: git fetch https://git.openjdk.org/skara pull/1414/head:pull/1414

PR: https://git.openjdk.org/skara/pull/1414