To create similar applications like when build with Tycho,
optional-requirements should be ignored by default when assembling the
bundles that are included in a plug-in based product-application
launched from the IDE.
If a user want's to include optional dependencies it can be re-enabled
in the launch-config dialog by checking the corresponding box.
The attribute is only set for newly created launch-configs to not change
the value of existing configs that were set manually.