removing clear from welcome

while it's superficially useful to start from a clean screen - it's
not actually helpful.

Quite often cake will issue setup errors which a user will not see
because they are immediately cleared. Users continue using the cli
unaware that they have (possibly significant) problems

lib/Cake/Console/Shell.php

@@ -200,7 +200,6 @@ class Shell extends Object {
  *
  */
 	protected function _welcome() {
-		$this->clear();
 		$this->out();
 		$this->out('<info>Welcome to CakePHP v' . Configure::version() . ' Console</info>');
 		$this->hr();