support map file from user for distributed s-net on lpel/lpel_hrc
 - use "-map <file" to specify the node location for snet entity
 - snet entity is identified by its locvec
 - SNetLocvecMapInit: read in map file for all entities
 - SNetLocvecGetMap: get the specified location for an entity. If not
   found, use the default location from snet file (e.g. app.snet)
 - currently support only static entities: parallel, box, filter,
   collector. This is because the locvec generated for dynamic entities
   are not accurate for distributed snet
modify to match with lpel when distinguishing wrapper and sosi
  - sosi and wrapper are distinguished by node location (worker id in
    lpel). sosi = -2, wrapper = -1
  - they behave the same, the only different is
    + output stream of sosi is considered as input of the program,
    + input stream of sosi is consider as output of program,
  - glob_input/output is sosi
  - input/output manager is normal wrapper