eson

I took a look at this library for configuring the express server in one of my projects. The plugin support with features like eson.ms is awesome. However the argv parsing is crude and eson doesn't allow me to parse any more than one config file (I'd like to save defaults in one, some env specific stuff in another, and then read a real user config file somewhere). Looking at nconf on the other hand it supports multiple file parsing, defaults, overrides, arg parsing using a full argv parser (optimist), but it has no support for plugins that support tweaking the values within the config files parsed. Instead of excelling in one area and trying to re-do another would you consider patching another library like nconf to support eson's type of plugins and making eson a collection of plugins.

This patch makes the serialization format for the eson Parser configurable. Users may provide their own and methods. This would allow one to swap in another implementation like json5, for instance.