Documentation and dependencies for v50r0 re-release.

ReleaseNotes/v50r0.md

-2018-04-16 DaVinci v50r0
+2018-04-20 DaVinci v50r0
 ========================
 
 Development release prepared on the master branch.
@@ -6,6 +6,10 @@ Development release prepared on the master branch.
 It is based on Gaudi v30r2, LHCb v50r0, Lbcom v30r0, Rec v30r0, Phys v30r0, Analysis v30r0 and Stripping v11r6,
 and uses LCG_93 with ROOT 6.12.06.
 
+- Removed Stripping test from nightlies
+  - See merge request lhcb/DaVinci!190
+- Cherry-pick MR !185 to master branch
+  - See merge request lhcb/DaVinci!189
 - Revert "Merge branch 'cherry-pick-5e437277' into 'master'"
   - See merge request lhcb/DaVinci!186
 - Cherry-pick MR !166 to master branch