Interface for allowing the underlying file storage to be changed

Adapter classes must implement the following functions:

• info(string or array of string or object keys, function callback)
• error(string or array of string or object keys, function callback)
• query(options, function callback)

options:

• level (optional) Level of logging you want to query for (info or error). Defaults to info.
• from (optional) Start time for the search. Defaults to 1 week ago.
• until (optional) End time for the search. Defaults to current time.
• order (optional) Direction of results returned, either “asc” or “desc”. Defaults to “desc”.
• size (optional) Number of rows returned by search. Defaults to 10

See FileLoggerAdapter.js for the default implementation