experimental use of binary mysqldump

git-svn-id: https://plugins.svn.wordpress.org/updraftplus/trunk@778804 b8457f37-d9ea-0310-8a92-e5e31aec5664
experimental use of binary mysqldump

git-svn-id: https://plugins.svn.wordpress.org/updraftplus/trunk@778806 b8457f37-d9ea-0310-8a92-e5e31aec5664