Issue #311: Add option --clean to remove cache and temporary files before building.
Issue #698: Do not enable --console with the --debug option.
Fix: Test case basic/test_module_attributes.py.
Fix: Test case test_onefile_relative_import2 for python 2.5.
Issue #673: Fix python 2.4 syntax in PEP302 importers.
Issue #673: Fix another python 2.4 syntax fix pyi_importers.py.
Fix: Ignore some tests for Python 2.4.
Fix: Ignore a test case for python 2.4.
Merge pull request #48 from matysek/develop

Add --clean option, restore py24  compatibility, etc.