Updated Pocket Plugin

Added a trim function to the URL in pocket.js to deal with links that have extra whitespace.  I have only found this to be a problem on Penny Arcade Reports, but it's definitely annoying.

I mentioned this in a [forum post] (http://tt-rss.org/forum/viewtopic.php?f=22&t=1548&p=7885#p7885), but I just found the repo.