Fixing bug where the file handle is not closed properly because the parentheses…

Fixing bug where the file handle is not closed properly because the parentheses are left off the call, telling Python to return a method but not call the method.

bin/ansible-vault

@@ -107,7 +107,7 @@ def get_opt(options, k, defval=""):
 def _read_password(filename):
     f = open(filename, "rb")
     data = f.read()
-    f.close
+    f.close()
     data = data.strip()
     return data