message: Bump clientversion to 4.0.0.1
diff: #define CLIENT_VERSION_MAJOR 4
  #define CLIENT_VERSION_MINOR 0
  #define CLIENT_VERSION_REVISION 0
  -#define CLIENT_VERSION_BUILD 0
  +#define CLIENT_VERSION_BUILD 1
  // Converts the parameter X to a string after macro replacement on X has been performed.
  // Don't merge these into one macro!
  