ci: update Travis configuration

 * Add testing on arm64, ppc64le, and s390x with select compiler versions
 * Drop all versions of gcc < 7 and clang < 5
 * Add clang 11 (development branch)
 * Reenable ASan on Linux with clang 7, the upstream bug has been fixed
 * Drop Xcode 9.2 (macOS 10.12 is no longer supported)
 * Upgrade Xcode 11 to 11.3
 * Workaround issue with missing /usr/local/opt/openssl on macOS
 * Various cleanups

Change-Id: Ifc7224cf3e79c74225efefc278bcb547ac862698
diff --git a/.jenkins.d/README.md b/.jenkins.d/README.md
index 5813349..6cba1e4 100644
--- a/.jenkins.d/README.md
+++ b/.jenkins.d/README.md
@@ -15,11 +15,11 @@
   * `[DISTRO_TYPE]`: `Ubuntu`
   * `[DISTRO_VERSION]`: `Ubuntu-16.04`, `Ubuntu-18.04`
 
-  Possible values for OS X / macOS:
+  Possible values for macOS:
 
   * `[OS_TYPE]`: `OSX`
   * `[DISTRO_TYPE]`: `OSX` (can be absent)
-  * `[DISTRO_VERSION]`: `OSX-10.11`, `OSX-10.12`, `OSX-10.13`
+  * `[DISTRO_VERSION]`: `OSX-10.12`, `OSX-10.13`, `OSX-10.14`
 
 - `JOB_NAME`: optional variable to define type of the job.  Depending on the defined job type,
   the build scripts can perform different tasks.