Fixes issue with links having to be declared in stopwords with the trail...

...ing period at the end
-------

Basically, the issue is that if I have links, say, `L<foo.com|http://bar.org>`, the original code tries to check `foo.com.` (note period at the end) as the stop word; fails, and changes the word to `foo.com.`

This is especially confusing when running things like `Test::Spelling` the output of which produces
```
# Errors:
#     com
#     doingitwrong
#     www
```
Even though `www.doingitwrong.com` AND `com doingitwrong www` are in the stopwords.
----
What the fix basically does is first check for whether the word is a stop word, then try and see whether it's got a dot in it, and if it does and the +dot version isn't a stop word, then leave the word as it were (i.e. do not set `$remainder` to $word+dot.

Dunno if that's the general idea of how that bit of code is meant to work, but I know that it fixes my link issue and doesn't add dots at the ends of words when I didn't want any :)