Fix #205 Use both DataMember and JsonPropertyName attributes on ECS types

[Mpdreamz]

• Move to JsonPropertyName
• Run code generation, moving to JsonPropertyName
• add more tests to ensure nested properties are written using declared names.

Update: Both JsonPropertyName and DataMember() need to be present to ensure compatibility with Json.NET and UTF8 json. This ensures the Elasticsearch Client up to version 7 can still read EcsDocument out of the box. We had integration tests checking deeply nested properties using the v7 Elasticsearch client.

cc @andreycha

[apmmachine]

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• Start Time: 2022-08-31T21:51:48.458+0000

• Duration: 19 min 18 sec

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Test	Results
Failed	0
Passed	96
Skipped	2
Total	98

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[Mpdreamz]

Self reviewing this @gregkalapos @z1c0 merging this in as all tests are green.