Added missing config parameter to config file.
Added code to exit shock server gracefully if mongo is not available. Added code to check for existence or at least creatibility of config defined directory paths.
Removed print statement of error message from db.Initialize because this error message should be printed by the code that called db.Initialize().
Added error return field to these functions so that these functions are called by goweb 2 when they are supposed to be.
Added return statements when appropriate.