Allow access to settings from ClojureScript

[jblomo]

There are probably many instances in which you'd like to share settings between server side and client side code. Right now settings.clj and settings/custom.clj are only used by server side clojure. All settings should probably not be shared: you don't want to ship your database settings to the client side.

One way to do this might be to use the Closure compiler's @define / --define semantics.

[jblomo]

I've written an initial version of this, but am open to changes.

Settings are organized into namespaces. Each namespace has an 'options Var that contain stuff like :dev-mode. Each settings namespace may load options differently, but typically they set up some defaults then merge in the options from "settings/[name].clj" in the classpath. The classpath includes test-resources and resources in development, but only resources in production. See (test-)resources/settings/global.clj as an example.

Sharing settings with CLJS is done at compile time. A clojure macro that is given a name and a namespace will def that name as the options map for the namespace. See cljs/src/initializer/settings-page.cljs for an example.