otb is marked for autoremoval from testing

[Debian testing autoremoval watch]

otb 6.0.0+dfsg-3 is marked for autoremoval from testing on 2017-09-04

It (build-)depends on packages with these RC bugs:
853386: insighttoolkit4: elastix: ftbfs with GCC-7
853419: insighttoolkit4: ginkgocadx: ftbfs with GCC-7
853454: insighttoolkit4: ftbfs with GCC-7
853460: insighttoolkit4: itksnap: ftbfs with GCC-7
853602: insighttoolkit4: otb: ftbfs with GCC-7
853658: shark: ftbfs with GCC-7