Allow to define file from which properties should be taken

If we have `propertyA` in `myPropFile1.properties` and `propertyA` in `myPropFile2.properties` we should be able to differentiate between those.

If I'm interested only in property value from the exactly known file I should be able to do something like:

```
@Inject
@ConfigurationValue(value = "propertyA", location="myPropFile1.properties")
String mySpecificProperty
```
