Fixing formatting in peg.py
Some PEP-8 fixes.
Improved default semantic action.

Converting terminal to a string as a default action.
Special handling for EOF and some improvement in debuging logging.
Refactoring PEG support
Automatic terminal suppressing during semantic analysis
Slightly improved debugging output
Reference resolving unification
Fixed bug in parser model construction

Fixed bug in parser model construction from python grammar description
with direct rule call.
Changed EOF string representation.
Updated PEG parser construction to take into account new improvements.
Separating unit and speed tests
Updating tests
Examples update
Removing print and disabling debuging in PEG parser construction