#702: fix minor issues with php_s rule

Unfortunately, I didn't catch these issues while reviewing #702.

After looking more closely at `php` options, `-S` requires additional
arguments (<address>:<port>) and `-s` may produce output if used that
way. So, matching ` -s ` seems to be better.

Also, `@for_app('php')` already asserts the presence of `php ` in the
command script. Matching `php -s` prevents the rule from fixing commands
like `php -t public -s 0.0.0.0:8080`.

thefuck/rules/php_s.py

@@ -3,11 +3,8 @@ from thefuck.utils import replace_argument, for_app
 
 @for_app('php')
 def match(command):
-    return "php -s" in command.script
+    return " -s " in command.script
 
 
 def get_new_command(command):
     return replace_argument(command.script, "-s", "-S")
-
-
-requires_output = False