RFR: 8266559: XPathEvaluationResult.XPathResultType.NODESET maps to incorrect type

[Joe Wang]

Makes a correction to XPathEvaluationResult.XPathResultType.NODESET mapping. Clarifies the supported types for the evaluateExpression methods.

Other changes were javadoc tag usages, e.g. s/the code tag/{@code

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

Commit messages:
 - 8266559: XPathEvaluationResult.XPathResultType.NODESET maps to incorrect type

Changes: https://git.openjdk.java.net/jdk/pull/4258/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=4258&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8266559
  Stats: 77 lines in 4 files changed: 28 ins; 0 del; 49 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4258.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4258/head:pull/4258

PR: https://git.openjdk.java.net/jdk/pull/4258