more copyedits

BUGS.md

@@ -107,7 +107,7 @@ on the `OutputPanel` object (which runs in the query process, but is supplied
 by a library, being present as a separate assembly from the query assembly) and
 calling the `Activate` method.
 
-The comment gives details about why I don”t think any currently available
+The comment gives details about why I don’t think any currently available
 good means of doing this exist. But as long as I’m doing that, Flood
 cannot have a stable release, as `OutputPanel.Activate` has the `internal`
 access modifier and it may be removed, or change behavior, in any future

doc/help.html

@@ -507,8 +507,8 @@ <h4 id="why-no-crash">
                title="Tail call - Wikipedia
 [redirect from &ldquo;Tail-call elimination&rdquo;]">Tail-call elimination</a>
             is not a solution, since even in languages that guarantee it in all
-            eligible cases, it can only apply to the the call that visits the
-            last neighbor enumerated. (C# never guarantees it anyway.)
+            eligible cases, it can only apply to the call that visits the last
+            neighbor enumerated. (C# never guarantees it anyway.)
           </p>
           <p>
             Some environments allow the call-stack size to be increased for a