FileConfiguration first cut to push

The push request contains my code for the FileConfiguration, the interfaces for Configuration and the testing code set as well as the test classes built to test the configuration code.
We already talked about how we can make that more generic. Since you require `String` objects for the `getProperty()` method I would recommend constants instead of Enums.

Example:
```java
   public class FileConfiguration implements Configuration {
      public static final String VERSION_NUMBER = "VersionNumber";
      public static final String PRE_PROCESSORS = "Pre-Processors";
      ...
      String versionNumber = properties.getProperty(VERSION_NUMBER);
      this.preProcessors = properties.getProperty(PRE_PROCESSORS);
      ...
```