Adds single page for items (ft: space separation for content descriptions)

## This pull request
We can talk about it in our meeting tomorrow (6:30p).  You can then accept this pull request and push up the git directory at the "make changes" time (4p Friday).  It looks like the branch can't automatically be merged for some reason, which is something I haven't run into before (but is totally normal), so there might be a bit of a git adventure.

## Single page for items
I added an items.php that will display just one item, based on the item id passed to it in the URL (e.g., jorgestradingpost.com/item.php?id=###).  Right now it just displays the card via contact.php or displays "result=null" if the id doesn't turn up an item.  We can talk about how to style this if you like in our meeting.

## Space separation for content descriptions
I added something that should turn the //r//n into <br><br> (using php's built in nl2br() function), whenever that comes up.  A little bonus.