Class ClientAppConfig

 clients.config format:

 Lines are of the form clientApp.x.prop=val, where x is the app number.
 App numbers MUST start with 0 and be consecutive.

 Properties are as follows:
        main: Full class name. Required. The main() method in this
              class will be run.
        name: Name to be displayed on console.
        args: Arguments to the main class, separated by spaces or tabs.
              Arguments containing spaces or tabs may be quoted with ' or "
        delay: Seconds before starting, default 120
        onBoot: {true|false}, default false, forces a delay of 0,
                overrides delay setting
        startOnLoad: {true|false} Is the client to be run at all?
                    Default true

 The following additional properties are used only by plugins:
        stopargs: Arguments to stop the client.
        uninstallargs: Arguments to stop the client.
        classpath: Additional classpath elements for the client,
                   separated by commas.

 The following substitutions are made in the args, stopargs,
 uninstallargs, and classpath lines, for plugins only:
        $I2P: The base I2P install directory
        $CONFIG: The user's configuration directory (e.g. ~/.i2p)
        $PLUGIN: This plugin's directory (e.g. ~/.i2p/plugins/foo)

 All properties except "main" are optional.
 Lines starting with "#" are comments.

 If the delay is less than zero, the client is run immediately,
 in the same thread, so that exceptions may be propagated to the console.
 In this case, the client should either throw an exception, return quickly,
 or spawn its own thread.
 If the delay is greater than or equal to zero, it will be run
 in a new thread, and exceptions will be logged but not propagated
 to the console.