Added support for config file properties injection

[galarragas]

I'm using subcut in some of my projects and I wanted to simplify the use case in which an object needs to retrieve some of the properties from configuration files.

I added some feature to implement injection similarly to the @value annotation in spring. For example:

class ToInject(implicit val bindingModule: BindingModule) extends Injectable {
    val stringProperty = injectProperty[String]("property1")
    val intProperty = injectProperty[Int]("property2")
    val longProperty = injectProperty[Long]("property3")
    val floatProperty = injectProperty[Float]("property4")
}

Allowing to inject in this way:

{
  implicit val bindingModule = newBindingModuleWithConfig(PropertiesConfigPropertySource.fromPath("src/test/resources/test.properties"))

   val configReaderInstance = new ToInject
}

It supports injection of basic types and allows generic types injection if a custom conversion function is provided.

I think it can help in simplify the code a lot. At least is doing it in my current work.

[lucamilanesio]

is the "import .....config.Undefined" really needed ? (as you imported the entire package before)

[lucamilanesio]

That's cool stuff, like it 👍