Improve image quality of thumbnail images

[komizutama]

This is likely a pretty simple fix. Imagemagick is used to handle the compression etc.

Minimum acceptance criteria

• spec thumbnail size to 250x250

stretch criteria

• Set up multiple sizes of thumbnails for different media types. This will eventually become a responsive app and building in this capability sooner rather than latter would be great.
  This may help:
  http://www.imagemagick.org/discourse-server/viewtopic.php?t=15438

[bglusman]

Yeah one line change to just replace 100x100 with 250x250 that seems good enough for now I'll PR that later or you can, trivial :-)

[komizutama]

Yeah I'm not worried. Just wanted to put all the information in one spot so I 1) didn't forget and 2) didn't have to dig through our slack convos to find it. heh