ACCEPT - issue EDEN-20: Missing header on PDF and SVG images 
https://internal.cida.usgs.gov/jira/browse/EDEN-20

Fixed -- switched to pyplot image hander.
ACCEPT - issue EDEN-20: Missing header on PDF and SVG images 
https://internal.cida.usgs.gov/jira/browse/EDEN-20

Compute logo position from image aspect ratio.
Merge pull request #39 from rhayes-cida/master

Fixed image logo bug (EDEN-20)