Add optional support for using getters in serialization

[stashuk]

Adding a getter support at @JsonField class-level annotation for serialization, updating SerializerTest to include new functionality.

[stashuk]

Agree, using GetterUUT now and passing annotation directly.

[ttung]

this looks good, but the rev graph is confusing. can you make one commit that adds the getter feature, and one commit that cleans up the code. either order is fine. :)

[stashuk]

Awesome, thanks! Changing to two commits now.

[stashuk]

Ping on merge.