Feat: add dots support for graphql keys

[vertex451]

Resolves the issue with labels that contains dots in names like http.bin.
GraphQL doesn't support bare identifiers, so instead of:

labels: {
    keyWithNoDot: "value",
}

we use this:

labels: [
	{key: "key.with.dots", value: "value"},
]

Changes

1. Added dots support in keys for:

• labels
• annotations
• nodeSelector
• matchLabel

2. Refactored schema handleObjectFieldSpecType method due to increased complexity. I took out checks into a natural named functions for a better readability.
3. Added integration test that creates a deployment with all 4 fields with dots and then retrieves it.
4. Docs.

[aaronschweig]

succeded by #296