Add a check for blank or entirely whitespace strings.

[ahallrq]

Allowing users to correct blank or whitespace strings results in a lot of spam.

Previously this would show:

   <user1> The quick brown fox jumps over the lazy dog.
   <user2> s/ /hello
<cloudbot> Correction, <user1> Thehelloquickhellobrownhellofoxhellojumpshellooverhellothehellolazyhellodog.

Now this should show:

   <user1> The quick brown fox jumps over the lazy dog.
   <user2> s/ /hello
<cloudbot> really dude? you want me to replace nothing with hello?

[edwardslabs]

I am conflicted on merging this. Not because I think it is a bad idea, I just know a lot of people love to use this "feature".

[ahallrq]

Fair enough. FWIW I've only ever seen it used for spam or to be annoying.