Squashed commit of the following:

commit bf505117a4d531a8d87f97e50c6ab81e7265d6cc
Author: Tom Hall <tahall256@gmail.com>
Date:   Sun Mar 10 15:53:20 2013 +0000

    No need to call startDownload twice in case of redirect.

commit 6f56d6ee4828fa23c226e7d6b1251aed5f42e7f6
Author: Tom Hall <tahall256@gmail.com>
Date:   Sun Mar 10 15:51:16 2013 +0000

    Inform thumbnail of started download

commit 68dcae8e03842b3f81c7842753cd3fc91376b91a
Author: Tom Hall <tahall256@gmail.com>
Date:   Sun Mar 10 13:47:36 2013 +0000

    Use QProgressBar in a QGraphicsProxyWidget to show progress. Proxy widget's parent is thumbItem, meaning it can be positioned and scaled within the thumbnail's coordinateses. Excluded from grid sort by checking for parent == 0.

commit 030326b8ac27174770544bf052a5710dc8521268
Author: Tom Hall <tahall256@gmail.com>
Date:   Sun Mar 10 12:32:43 2013 +0000

    Remove debug spam

commit 7a949cc4f3e07ec7f2ad5716ba08c931ffa1448f
Author: Tom Hall <tahall256@gmail.com>
Date:   Sun Mar 10 12:29:10 2013 +0000

    In case of error downloading image, Show error dialog and don't dim the thumbnail.

commit f21926ab72a7ef39860cae1127972b14f64586f0
Author: Tom Hall <tahall256@gmail.com>
Date:   Sun Mar 10 11:56:36 2013 +0000

    In fact, set the url to the redirect url and use the original download function.

commit 182f8d545fd8dbf020cbddc344b1279702004cdc
Author: Tom Hall <tahall256@gmail.com>
Date:   Sun Mar 10 11:50:45 2013 +0000

    If redirected, just download the redirect url in the same way as the original.

commit f6b0a5c53ac0b1b0d699b22954e6ec655298a59b
Author: Tom Hall <tahall256@gmail.com>
Date:   Sun Mar 10 11:43:23 2013 +0000

    Don't scale thumbnail items, scale the pixmap inside.

commit 38329f748b9c30bf527b1fbea625a3b239986d81
Author: Tom Hall <tahall256@gmail.com>
Date:   Sun Mar 10 01:14:09 2013 +0000

    use rect to position text

commit d9cd5b00f2e078f30b394de85d19192a03c89742
Author: Tom Hall <tahall256@gmail.com>
Date:   Sun Mar 10 01:04:46 2013 +0000

    Print progress %

commit ad3e8e72ef30dd1bb94a063d20eb7edf31e126ba
Author: Tom Hall <tahall256@gmail.com>
Date:   Sun Mar 10 00:59:37 2013 +0000

    Show download progress. TODO: Size depends on thumb scale.

Add Progress bars when downloading images. Show error message if error when downloading. Fix redirects.