Patch: blog list in a table, check for invalid user

Attached patch for the 6.x branch does a few things:

• makes the blog list a table so it is a formatted a little nicer (in my opinion)
• adds some checks for invalid user names to avoid sql calls for nonexistent users (which generates errors). this also prints a message that the user doesn't exist
• some basic source reformatting for readability

I should have made these distinct patches, but... it is it what it is!