Bugfixes

• correctly handle errors thrown during parser/generator creation
  • e. g. validation errors for asset module options
• use a better automatic runtime name for workers
  • not too long to cause filename problems
• no longer assume assets do not get removed when the compiler is running
  • Using output.clean is against this assumption
  • It fixes a bug where assets are missing, when removed and readded to the compilation
• fix a problem when chained dependOn, which causes too many modules being included in entrypoints