RFR: 1325: Update Skara to recognize the FX 8uNNN-bXX tag format

[Erik Joelsson]

Add support for the legacy (8u) jfx tag format.

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Commit messages:
 - Simplify regexp a bit
 - SKARA-1325

Changes: https://git.openjdk.java.net/skara/pull/1279/files
 Webrev: https://webrevs.openjdk.java.net/?repo=skara&pr=1279&range=00
  Issue: https://bugs.openjdk.java.net/browse/SKARA-1325
  Stats: 12 lines in 2 files changed: 11 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/skara/pull/1279.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/1279/head:pull/1279

PR: https://git.openjdk.java.net/skara/pull/1279