Update CHANGELOG.md

CHANGELOG.md

+* 2019-06-06 - First Beta
+* * Renamed packages and files, replaced references to Symbiosis with Sympl.
+* * * bytemark-symbiosis -> sympl-core
+* * * symbiosis-httpd -> sympl-web
+* * * symbiosis-email -> sympl-mail
+* * * symbiosis-ftpd -> sympl-ftp
+* * * symbiosis-meta -> sympl-core
+* * * symbiosis-* -> sympl-*
+* * Renamed command-line tools, with new package names, added symlinks from old names.
+* * /etc/symbiosis is now /etc/sympl, with symlink for compatibilty.
+* * Folded old metapackages into relevant packages.
+* * Dropped support for old Exchange Activesync.
+* * Dropped support for XMPP.
+* * A lot of tidying up.
 * 2019-05-28 - Implemented autotest suite, updated docs.
 * 2019-04-16 - Fixed Gitlab CI
 * 2019-04-13 - Initial fork from GitHub