Update notes for submitted changes

* Update Jetty to 9.4.20.v20190813
* Delete outdated Orbit target platform definitions
* Update target platform to S20190819183153 (2019-09 M3)
* Exclude SecurityManagerTest from bazel test run

89/a041cdd7a732c6c97976f862f57f6e7a17f450

@@ -0,0 +1,7 @@
+Verified+1: JGit Bot <jgit-bot@eclipse.org>
+Code-Review+2: David Pursehouse <david.pursehouse@gmail.com>
+Submitted-by: David Pursehouse <david.pursehouse@gmail.com>
+Submitted-at: Mon, 26 Aug 2019 07:02:15 -0400
+Reviewed-on: https://git.eclipse.org/r/148307
+Project: jgit/jgit
+Branch: refs/heads/master

cb/208fb3ca130a2241bef3f3a33d54269d3a14ba

@@ -0,0 +1,7 @@
+Verified+1: JGit Bot <jgit-bot@eclipse.org>
+Code-Review+2: David Pursehouse <david.pursehouse@gmail.com>
+Submitted-by: David Pursehouse <david.pursehouse@gmail.com>
+Submitted-at: Mon, 26 Aug 2019 07:02:15 -0400
+Reviewed-on: https://git.eclipse.org/r/148312
+Project: jgit/jgit
+Branch: refs/heads/master

cd/647df6d746e7ed95e2b543863c23656fbf1a0f

@@ -0,0 +1,7 @@
+Verified+1: JGit Bot <jgit-bot@eclipse.org>
+Code-Review+2: David Pursehouse <david.pursehouse@gmail.com>
+Submitted-by: David Pursehouse <david.pursehouse@gmail.com>
+Submitted-at: Mon, 26 Aug 2019 07:02:15 -0400
+Reviewed-on: https://git.eclipse.org/r/148306
+Project: jgit/jgit
+Branch: refs/heads/master

ce/e26c00372db1e0e4a9c3c68238607190380451

@@ -0,0 +1,7 @@
+Verified+1: JGit Bot <jgit-bot@eclipse.org>
+Code-Review+2: David Pursehouse <david.pursehouse@gmail.com>
+Submitted-by: David Pursehouse <david.pursehouse@gmail.com>
+Submitted-at: Mon, 26 Aug 2019 07:02:15 -0400
+Reviewed-on: https://git.eclipse.org/r/148311
+Project: jgit/jgit
+Branch: refs/heads/master