Update alert text for new thread types

[Paul B]

So instead of:
"XenForo started a thread called XF 2.2 Assorted improvements. There may be more posts after this."

If it was a poll it would be:
"XenForo posted a poll called XF 2.2 Assorted improvements. There may be more posts after this."

An article:
"XenForo posted an article called XF 2.2 Assorted improvements. There may be more posts after this."

And so on.

 

[beerForo]

Can even tidy it up... "called" is kinda weird...

"XenForo posted the poll XF 2.2 Assorted improvements. There may be more posts after this."

"XenForo posted the article XF 2.2 Assorted improvements. There may be more posts after this."