RFR: Added section on maintainer-pain [v2]

[Jesper Wilhelmsson]

> Added section on maintainer-pain

Jesper Wilhelmsson has updated the pull request incrementally with one additional commit since the last revision:

  Refer to ProblemList section

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Changes:
  - all: https://git.openjdk.java.net/guide/pull/37/files
  - new: https://git.openjdk.java.net/guide/pull/37/files/88322e97..ac1986b4

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=guide&pr=37&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=guide&pr=37&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/guide/pull/37.diff
  Fetch: git fetch https://git.openjdk.java.net/guide pull/37/head:pull/37

PR: https://git.openjdk.java.net/guide/pull/37