[JAVA] equals and hashCode for models with byte[] vars

[bmordue]

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Description of the PR

For models with a byte array field, the generated equals and hashCode methods are not correct. This change modifies the template to use Array.equals and Arrays.hash for byte array variables.

I think this goes at least some way to being a fix #3731

cc @bbdouglas @JFCote @sreeshas @jfiala @lukoyanov @cbornet

[bmordue]

I based my branch off #6758 to avoid a bunch of unwanted changes in the sample clients.

[bmordue]

I don't know how to cover the three cases of isBinary, isByteArray and "is neither binary nor byte array" with a mustache template. Any tips for that?
Does it need a new variable property (maybe isArray)?

[wing328]

Does it need a new variable property (maybe isArray)?

@bmordue Would isListContainer meet your requirement?

[wing328]

I'll cherry-pick 533816c later as this PR contains too many changes not relevant to the fix.

[wing328]

I don't know how to cover the three cases of isBinary, isByteArray and "is neither binary nor byte array" with a mustache template. Any tips for that?

{{^isBinary}}{{^isByteArray}} ..... {{/isByteArray}}{{/isBinary}} to cover the 3rd case.

[bmordue]

I'm closing this PR: #7341 is the same work in a cleaner PR.