Missing Dictionary>>isHealthy

[j4yk]

These methods send #isHealthy, but it is not implemented in Squeak:

• Dictionary>>#stonPostReferenceResolution
• Set>>#stonPostReferenceResolution
• STONReaderTest>>#testDictionaryWithIndirectReferenceKeys
• STONReaderTest>>#testDictionaryWithReferenceKeys
• STONReaderTest>>#testSetWithIndirectReferenceElements
• STONReaderTest>>#testSetWithReferenceElements

[j4yk]

@fniephaus Looks like you already added that on https://github.com/fniephaus/ston/tree/fniephaus-patch-3

How do you suggest we best integrate it? Merge the branch or "cherry-pick" the methods?

[fniephaus]

Feel free to cherry-pick, seems to be the easiest solution.