Increment version to 5.4.3.0 for release and update copyright year to…

… 2023.

configure.ac

@@ -2,10 +2,10 @@ dnl require autoconf 2.60 (AS_ECHO/AS_ECHO_N)
 AC_PREREQ([2.60])
 define(_CLIENT_VERSION_MAJOR, 5)
 define(_CLIENT_VERSION_MINOR, 4)
-define(_CLIENT_VERSION_REVISION, 2)
+define(_CLIENT_VERSION_REVISION, 3)
 define(_CLIENT_VERSION_BUILD, 0)
 define(_CLIENT_VERSION_IS_RELEASE, true)
-define(_COPYRIGHT_YEAR, 2022)
+define(_COPYRIGHT_YEAR, 2023)
 define(_COPYRIGHT_HOLDERS,[The %s developers])
 define(_COPYRIGHT_HOLDERS_SUBSTITUTION,[[Gridcoin]])
 AC_INIT([Gridcoin],[_CLIENT_VERSION_MAJOR._CLIENT_VERSION_MINOR._CLIENT_VERSION_REVISION],[https://github.com/gridcoin/Gridcoin-Research/issues],[gridcoin],[https://gridcoin.us/])