message: Bump master build to v1.0.3.99.
diff: dnl require autoconf 2.60 (AS_ECHO/AS_ECHO_N)
  AC_PREREQ([2.60])
  define(_CLIENT_VERSION_MAJOR, 0)
  -define(_CLIENT_VERSION_MINOR, 0)
  -define(_CLIENT_VERSION_REVISION, 0)
  +define(_CLIENT_VERSION_MINOR, 1)
  +define(_CLIENT_VERSION_REVISION, 3)
  define(_CLIENT_VERSION_BUILD, 99)
  define(_CLIENT_VERSION_IS_RELEASE, false)
  define(_COPYRIGHT_YEAR, 2019)
  