Merge branch 'ExternalsUpdateForQt-master-20170615' into 'master'

Externals updates for Qt5/VP1, master branch (2017.06.15.)

See merge request !2720

Former-commit-id: 3df37611

Projects/AnalysisBase/externals.txt

 # Versions of the various externals to build before starting the build of
 # this project, when doing a full stack nightly build.
+#
+# Remember that when specifying the name of a branch, you *must* put
+# an "origin/" prefix before it. For tags however this is explicitly
+# forbidden.
 
-AnalysisBaseExternalsVersion = 6cbde55c
+# The version of atlas/atlasexternals to use:
+AnalysisBaseExternalsVersion = 3ddfb26b

Projects/AthSimulation/externals.txt

@@ -5,5 +5,8 @@
 # an "origin/" prefix before it. For tags however this is explicitly
 # forbidden.
 
-AthSimulationExternalsVersion = 6cbde55c
+# The version of atlas/atlasexternals to use:
+AthSimulationExternalsVersion = 3ddfb26b
+
+# The version of atlas/Gaudi to use:
 GaudiVersion = v28r2.005

Projects/Athena/externals.txt

@@ -5,5 +5,8 @@
 # an "origin/" prefix before it. For tags however this is explicitly
 # forbidden.
 
-AthenaExternalsVersion = 288f043b
+# The version of atlas/atlasexternals to use:
+AthenaExternalsVersion = 3ddfb26b
+
+# The version of atlas/Gaudi to use:
 GaudiVersion = v28r2.005