RFR: JDK-8263188: JSSE should fail fast if there isn't supported signature algorithm

[John Jiang]

If signature_algorithms extension is present, but the algorithms are unreconginzed or unsupported, JSSE peers should send fatal alert immediately.
For example, in this case, it's unnecssary to try to produce ServerHello, Certificate and ServerKeyExchange messages.

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Commit messages:
 - JDK-8263188: JSSE should fail fast if there isn't supported signature algorithm

Changes: https://git.openjdk.java.net/jdk/pull/2876/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2876&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8263188
  Stats: 9 lines in 1 file changed: 8 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2876.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2876/head:pull/2876

PR: https://git.openjdk.java.net/jdk/pull/2876