make flow clearer
move away from Cable
inline
remove datastore
basic server uploading
log error but dont qui
handle both bmp and png file types
add support for bmp captures
move conversion to worker
experimental binary diff

Conflicts:
	recall/main.go
capture pngs

PNGs offer smaller file sizes but poor binary diffs
BMPs are large, but the diffs are TINY.
add Capture type
put in captures dir
don't write patches
rm noisy log statement
add a buffer
back off when server is unavailable

TODO save captures to disk until they can be uploaded
parallelize uploading