[doc] Clarify interpretation of verifyClient (#1994)

Prior to this commit, the documentation for the `verifyClient` option
was somewhat confusing due to its use of the passive voice and an
uncommon interpretation of the term "arguments".

Explain the way `ws` interprets the value of `verifyClient` using an
active voice and more traditional meanings of "parameters" and
"arguments".

doc/ws.md

@@ -99,7 +99,7 @@ to share a single HTTP/S server between multiple WebSocket servers.
 > more details.
 
 If `verifyClient` is not set then the handshake is automatically accepted. If it
-is provided with a single argument then that is:
+has a single parameter then `ws` will invoke it with the following argument:
 
 - `info` {Object}
   - `origin` {String} The value in the Origin header indicated by the client.
@@ -110,7 +110,8 @@ is provided with a single argument then that is:
 The return value (`Boolean`) of the function determines whether or not to accept
 the handshake.
 
-if `verifyClient` is provided with two arguments then those are:
+If `verifyClient` has two parameters then `ws` will invoke it with the following
+arguments:
 
 - `info` {Object} Same as above.
 - `cb` {Function} A callback that must be called by the user upon inspection of