RFR: 6588: Move JMC core to JDK 8 [v3]

Mon Jan 18 19:57:50 UTC 2021

> WIP. Now that core requires JDK 8, we can make it a little bit more easygoing when using streams. I'm thinking it would be nice to remove the need for the StreamModel altogether as well.

Marcus Hirt has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains eight commits:

 - Merge branch 'master' into 6588-core-jdk8-cleanup
 - Formatting
 - Adding values()
 - Supporting streaming in IItemIterable
 - Additional cleanup
 - Inlining stream
 - First move
 - 6588: Initial cleanup

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Changes: https://git.openjdk.java.net/jmc/pull/194/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jmc&pr=194&range=02
  Stats: 964 lines in 71 files changed: 488 ins; 414 del; 62 mod
  Patch: https://git.openjdk.java.net/jmc/pull/194.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/194/head:pull/194

PR: https://git.openjdk.java.net/jmc/pull/194