Add a chapter about Running or debugging gradle under Eclipse

[zosrothko]

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Add a chapter about Running or debugging gradle under Eclipse. Fix typo for invoking gradlew.bat under Windows.

[eriwen]

Have you found this to work in practice? My understanding was that this doesn't currently do the right thing for the gradle/gradle build.

[zosrothko]

Yes you are right. Running/Debugging the gradle build itself under Eclipse does not work, but this works for all others builds. This allows to degug gradle itself.

[eriwen]

@zosrothko Thank you. The content looks good except that I want to confirm with you that ./gradlew eclipse works. Once you confirm that works on gradle/gradle I'll merge this.

[zosrothko]

Yes, both

./gradlew eclipse     // on *nix
gradlew eclipse       // on windows

are working

[eriwen]

Merged with 02097f7 — thank you @zosrothko!