By moving shelve retrieval details to configuration_retrieve()
into configuration.py, the top-level SConstruct can now get full
configuration object from shelve.
Created a config directory for configuration files.
Moved all absolute path variables to a projpaths.py file
All scripts can now universally learn absolute paths via projpaths.py
Moved the config_symbols class to the configuration.py file.
Moved libs to loader since they are only referred by the loader
