#67
1. Renamed `FilterFactory` static class to `Filters` for desired readability / syntax.
2. Renamed the filter method `IncludeScriptNamesInFile` to `OnlyIncludeScriptNamesInFile`
3. Added two Filter methods to the Filters class - `ExcludeScripts` and `OnlyIncludeScripts`
4. Added two Unit tests for the above two filter methods.
5. Added a constructor overload to `FileSystemScriptProvider` that accepts a filter.
6. Changed FileSystemScriptProvider `GetScripts` to apply the filter if there is one before returning scripts.
7. Added an overload of `WithScriptsFromFileSystem` that takes a filter, to the `StandardExtensions` static class (Fluent  API)
8. Added a unit test for `FileSystemScriptProvider` that checks that when the new constructor is used that takes a filter, the filter is executed, and doesn't modify script ordering.
9. Added XML comments to the Filter Methods describing usage, params etc.