[extras] TOML advanced map support

[Gmugra]

@Config(sources="classpath:/myconfig.toml")
public interface ConfigMap {

    Map<Integer, String> myMap();
}

At the moment, only way to provide map is "properties" style. e.g. myconfig.toml must be so:

myMap = "8000|One,8001|Two"

Idea is to provide special support for key-postfix e.g. ".map":

[myMap.map]
8000 = "One"
8001 = "Two"

This should porvide same result as before: property with name myMap (without postfix) with Map inside.

Sure is should work with complex use case like array as value with complex object like key. e.g. :

@Config(sources="classpath:/myconfig.toml")
public interface ConfigMap {

    Map<UUID, List<Integer>> complex();
}

[complex.map]
46400000-8cc0-11bd-b43e-10d46e4ef14d = [ 8000, 8001, 8002 ]
46400000-8cc0-11bd-wert-10d46e4ef14d = [ 6000, 6001, 6002 ]