Begin 3.19 release versioning

Source/CMakeVersion.cmake

@@ -1,8 +1,8 @@
 # CMake version number components.
 set(CMake_VERSION_MAJOR 3)
-set(CMake_VERSION_MINOR 18)
-set(CMake_VERSION_PATCH 20201008)
-#set(CMake_VERSION_RC 0)
+set(CMake_VERSION_MINOR 19)
+set(CMake_VERSION_PATCH 0)
+set(CMake_VERSION_RC 0)
 set(CMake_VERSION_IS_DIRTY 0)
 
 # Start with the full version number used in tags.  It has no dev info.