Merge branch 'dario'

This is a merge of patches sent by Dario with some fixes and comments added by me.

* Merged commits:
  First stub of the feedback API.
  Different solution for dedaling with csects serialization.
  Added comment for a possible bug
  Better dealing with attr = NULL bug.
  Memory leak in shared objects removed.
  Small fixes from the prev. commit.
  Testcase and bugfixes for synchronization and shared objects.
  Added comments on possible changes in csect IDL block
  Shared Objects.
  Synchronization objects.
  Updates to the previous commit: added documentation and fixed bugs
  Further improvements in core API implementation.
  Resource independent thread functions and synch/shared objects stub.
  Bugfix and FRSH thread function generalization.