Add "path" in phpdoc of connections supporting UNIX domain sockets.

lib/Predis/Connection/PhpiredisConnection.php

@@ -37,6 +37,7 @@ use Predis\Command\CommandInterface;
  *  - scheme: it can be either 'tcp' or 'unix'.
  *  - host: hostname or IP address of the server.
  *  - port: TCP port of the server.
+ *  - path: path of a UNIX domain socket when scheme is 'unix'.
  *  - timeout: timeout to perform the connection.
  *  - read_write_timeout: timeout of read / write operations.
  *

lib/Predis/Connection/PhpiredisStreamConnection.php

@@ -37,6 +37,7 @@ use Predis\Command\CommandInterface;
  *  - scheme: it can be either 'tcp' or 'unix'.
  *  - host: hostname or IP address of the server.
  *  - port: TCP port of the server.
+ *  - path: path of a UNIX domain socket when scheme is 'unix'.
  *  - timeout: timeout to perform the connection.
  *  - read_write_timeout: timeout of read / write operations.
  *  - async_connect: performs the connection asynchronously.

lib/Predis/Connection/StreamConnection.php

@@ -23,6 +23,7 @@ use Predis\Iterator\MultiBulkResponseSimple;
  *  - scheme: it can be either 'tcp' or 'unix'.
  *  - host: hostname or IP address of the server.
  *  - port: TCP port of the server.
+ *  - path: path of a UNIX domain socket when scheme is 'unix'.
  *  - timeout: timeout to perform the connection.
  *  - read_write_timeout: timeout of read / write operations.
  *  - async_connect: performs the connection asynchronously.