[MRG] add support for file_bytes argument with managed_file_context()

[cscanlin]

Fixes https://github.com/camelot-dev/camelot/issues/170 and https://github.com/camelot-dev/camelot/issues/245

[chris-decker]

I needed this functionality and since the original author hasn't yet merged it I cloned the repo and merged locally. Seems to be working as intended, thanks for contributing.

[clcarver1130]

Is this still stalled? Would love this functionality if still possible

[cscanlin]

Unfortunately this repo looks to be somewhat abandoned, @vinayak-mehta has not merged any code since July 2021.

It's a really useful tool, so it would be a shame to let it decay. Does anybody have interest in being a maintainer?

[ramSeraph]

Consider starting a discussion on gitter?