Config data should be in compiled code

[jaynel]

The current approach to config data is using the application_controller get_env utilities. These require an ets access to get the information. Rather than adding an extra ets fetch before every ets_buffer queue fetch (to find out the name of the ets_buffer), it would be better to use compiled code. Compiled code is available everywhere concurrently, whereas accessing the same key on an ets table is serialized with an internal lock.

[jaynel]

Compiled code is now used for config, but a simple example of relup / reldown is needed to allow hot code loading of the config for easier control of the runtime.