[Build] Bump version to 4.2.0

Update version, enable release, and set rc1

configure.ac

@@ -1,11 +1,11 @@
 dnl require autoconf 2.60 (AS_ECHO/AS_ECHO_N)
 AC_PREREQ([2.60])
 define(_CLIENT_VERSION_MAJOR, 4)
-define(_CLIENT_VERSION_MINOR, 1)
-define(_CLIENT_VERSION_REVISION, 99)
+define(_CLIENT_VERSION_MINOR, 2)
+define(_CLIENT_VERSION_REVISION, 0)
 define(_CLIENT_VERSION_BUILD, 0)
-define(_CLIENT_VERSION_RC, 0)
-define(_CLIENT_VERSION_IS_RELEASE, false)
+define(_CLIENT_VERSION_RC, 1)
+define(_CLIENT_VERSION_IS_RELEASE, true)
 define(_COPYRIGHT_YEAR, 2020)
 AC_INIT([PIVX Core],m4_join([.], _CLIENT_VERSION_MAJOR, _CLIENT_VERSION_MINOR, _CLIENT_VERSION_REVISION, m4_if(_CLIENT_VERSION_BUILD, [0], [], _CLIENT_VERSION_BUILD))m4_if(_CLIENT_VERSION_RC, [0], [], [rc]_CLIENT_VERSION_RC),[https://github.com/pivx-project/pivx/issues],[pivx],[https://pivx.org/])
 AC_CONFIG_SRCDIR([src/main.cpp])