RFR: 7348: JMC preference options are duplicated [v3]

[Guru Hb]

> "General" , "Appearance" and "Keys" had duplicate entry . This was due to some in consistence "org.eclipse.ui.*" Components were used (one with older + latest version which is causing duplicate entry). 
> 
> Solution : adding "resolution:=optional" resolves the duplicate entry. ~~Restricted the Eclipse UI components to v3.2.0 and less than equal to 4.0.0.~~

Guru Hb has updated the pull request incrementally with one additional commit since the last revision:

  Copyright notice format corrected

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Changes:
  - all: https://git.openjdk.java.net/jmc/pull/289/files
  - new: https://git.openjdk.java.net/jmc/pull/289/files/ffb3ebc1..6db4e6c7

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jmc&pr=289&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jmc&pr=289&range=01-02

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jmc/pull/289.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/289/head:pull/289

PR: https://git.openjdk.java.net/jmc/pull/289