- Steven, Nico

- all cdist cores change to the local or remote base dir before excution
  of non-core (i.e. manifests, gencode, ...) executables

- non-core executables get helper information via environment variables:

   general explorers: __explorers
   initial manifest: __manifests
   type manifests:  __object, __object_id
   type explorers:  __object, __object_id, __type_explorers
   type codegen:  __object, __object_id
   type code:  -

