Release Candidate 6.6-RC2

We are ready to create the Release Candidate (RC2) for version 6.6. The RC is deployed before the Release to catch eventual bugs.

The following steps need to be performed :

1. Create the new release branch
2. Update OTB/CMakeLists.txt version numbers in branch 'develop' to the next development version
3. Update OTB/CMakeLists.txt version numbers in branch 'release-6.6' to 6.6.0
4. Update dashboard scripts to support new version numbers
5. Update the SuperBuild archive
6. Send an email to otb-developers to announce the beginning of the release process
7. Gather feedback on bugs that need to be fixed, make a public list and track the fixes to be able to get progress info during the release
8. Run Debian spelling checker
9. Run shellcheck script from OTB-Devutils/Scripts/
10. Update translation for Monteverdi & Mapla
11. Update FAQ, Cookbook and Software Guide (download, installation and compilation sections, contributor list) in both develop and release branch.
12. Update GIT_TAG for all official remote modules
13. Sanity Check the binary packages
14. Windows
15. Linux
16. Mac
17. Tag the release branches
18. Prepare and upload source packages
19. Promote nightly packages
20. Update documentation :
21. Software Guide
22. Cookbook
23. Doxygen
24. Application online documentation
25. Send RC announcement email (including updated checkout commands).