Run remaining equinox backend services as JAR products

[ndoschek]

With #457 we switched Model Server and GLSP backend server products from equinox to pure JAR products.
For easier maintenance we should switch to JAR products also for the remaining backend services:

• wf-lsp
• wf-analyzer
• cpp-codegen
• java-codegen

See the current product definitions in https://github.com/eclipse-emfcloud/coffee-editor/tree/master/backend/releng/org.eclipse.emfcloud.coffee.product