Move session save path to tmp

`$GLOBALS['TMP_DIR']` was empty causing LSP page sessions to incorrectly save in `lsp_data`.

Changing to the same location as the rest of the site prevents the inode filling up since we have a cron job written by network redux called `php-session-cleanup.sh` which cleans up sesssion files over 10 days.

Closes #173.

public/lsp/index.php

@@ -4,7 +4,7 @@
 
 ini_set('session.use_trans_sid', false);
 ini_set('session.save_handler', 'files');
-ini_set('session.save_path', $GLOBALS['TMP_DIR']);
+ini_set('session.save_path', $_SERVER["DOCUMENT_ROOT"] . '/../tmp/');
 ini_set('arg_separator.output', '&');
 
 session_start();