build: set CLIENT_VERSION_RC to 0 pre-final

Tree-SHA512: 3d071f93f6fc5b30ccfb3ca34d7e050370d2d6201aca892503a4300a761116d69ceed7c770283581fcce0ce78ff7c0a6820db8600877d09fba9ed0cd488f4bf7

Author: laanwj

configure.ac

@@ -4,7 +4,7 @@ define(_CLIENT_VERSION_MAJOR, 0)
 define(_CLIENT_VERSION_MINOR, 19)
 define(_CLIENT_VERSION_REVISION, 0)
 define(_CLIENT_VERSION_BUILD, 0)
-define(_CLIENT_VERSION_RC, 3)
+define(_CLIENT_VERSION_RC, 0)
 define(_CLIENT_VERSION_IS_RELEASE, true)
 define(_COPYRIGHT_YEAR, 2019)
 define(_COPYRIGHT_HOLDERS,[The %s developers])