RAW converter Kipi plugin re-written from scratch

Since Paco work on digiKam/DigikamImagePlugins 0.9.0-beta2 tarballs, svn is frozen until this release is completed.

This week i have toggle to kipi plugins to re-write completly the RAW converter plugin. See below the new features :

- Fully compatible with the last dcraw version available .
- A lots of new conversion options (look the screenshoots at this url).
- Color space profile saved to target images.
- Metadata preservation during conversion (Exif/makernote) using Exiv2 library (JPEG/PNG).
- Using multithreading.