Decouple JDL from generators.

[mshima]

Overview of the feature request

JDL and generators should be independent.

Motivation for or Use Case

Related issues or PR

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[Tcharl]

Ideally, each jdl statements and values of relative to each generators should be included in the respective generator.
i.e. the JDL's clientFrameworkType should be in generator-client, jdl acting as an interpretation engine (ast)