Revert "svn: prevent hanging when reading output from pipes"

This reverts commit 0c060a6 (#254).

As per discussion in #259, use of 'a' for pipe type is not documented in
the PHP manual [1], and the proc_open() call does not work with it
(STDERR returns no output).

[1]: http://php.net/manual/en/function.proc-open.php

Author: dregad

SourceSVN/SourceSVN.php

@@ -324,7 +324,7 @@ private function svn_run( $p_cmd, $p_repo = null )
 
 		$t_svn_proc = proc_open(
 			$t_svn_cmd,
-			array( array( 'pipe', 'r' ), array( 'pipe', 'w' ), array( 'pipe', 'a' ) ),
+			array( array( 'pipe', 'r' ), array( 'pipe', 'w' ), array( 'pipe', 'w' ) ),
 			$t_pipes
 		);