Improved Auth related module implementation by having a way to change settings like token, max age.
- use CMS_SETUP.site_id and related "auth.$module.token" ... configuration values.
- removed related CMS_..._CONSTANTS classes.
For auth session module, use auth_session as table name, and use VARCHAR(64).
Extracted sql from blog module, and store it under site/scripts/install.sql .
Renamed a few $modulename.sql as install.sql
