Adding optional support for joda-time's DateTime class

[jthoenes]

• we check, if JavaTime is available in class path
• if it is, we handle it exactly like java.util.Date

[vojtechhabarta]

@jthoenes thanks for your PR.

I don't want to process types from external libraries in DefaultTypeProcessor. But in this case it is just one class (org.joda.time.DateTime) so lets leave it in DefaultTypeProcessor for now and it can be refactored into some new TypeProcessor later.

[vojtechhabarta]

Part of 1.22.307 release.

[vojtechhabarta]

@jthoenes I removed support for org.joda.time.DateTime type in v1.28.343 because I want to minimize specific library handling in typescript-generator core. Sorry for that.

Instead I added support for java.time date types (similar to joda types but part of Java 8). All types that implement java.time.temporal.Temporal are now considered to be date types. Jackson2 supports these classes using com.fasterxml.jackson.datatype:jackson-datatype-jsr310 module which can be added to Jackson2 using

new ObjectMapper().registerModule(new JavaTimeModule())
// or
new ObjectMapper().findAndRegisterModules()

Joda's org.joda.time.DateTime still can be used. It can be mapped for example to string using customTypeMappings parameter. Here is Maven configuration sample:

<configuration>
    <customTypeMappings>
        <mapping>org.joda.time.DateTime:string</mapping>
    </customTypeMappings>
    ...
</configuration>