Support custom error message

[luka5]

Currently all the useful error messages are hardcoded.
To support custom error message, e.g. localized, it would be great having an optional parameter defining the messages.

[rpedela]

+1

[adrianheine]

+1

[atrniv]

+1

[syadykin]

+1

[shachr]

+1

It would be best to map all errors into codes and support a custom translation function:

js.translateErrorCode( function( code, defaultErrorMessage, callback ){
     var locale = process.domain.getLocale();
     var errorMessages = require("./errorMessages/"+ locale);
     callback( null, errorMessages[code] );
});

[iliocatallo]

+1