remove fd import and print lib's log in print_emitter()
add library's log
add lib's log
add log in FD.close()
add context methods
add log in pop lib
add log in smtp lib
new stats module
add new basic classes: Object and Error
new module for expressions generation
add import in pysec and add Expression's doc
add import in pysec and add Expression's doc
fix __div__ call and fix Expression.compute() to avoid issue4806

http://bugs.python.org/issue4806
add __all__ and const maker
new module to check arguments
add __all__ and default values for start and stop
default value for size in pread()
add __all__
add CheckRuleError exception
add __len__