Code cleaning and organizing

- Having one chain includes was a bad idea and a maintaining nightmare.
  It is now fixed.

- Detailed error logging for errno was another bad idea. No longer needed.

- Error logging has become much better organized and got rid of all those
  ugly macros.

- Code corrections here and there

- Introduced the beginning of an atomic header
Renaming error.h to the log module and more cleaning all around. Log module needs more work