Support file schemes in SimpleBitmapLoader

[tzugen]

Fixes #108

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[christosts]

Please sign the license agreement and I'll merge the pull-request.

[added] Also, the PR should target the main branch, not the release one.

[tzugen]

Done!

[christosts]

I've left a comment on the code, I was wondering if you saw it?

[tzugen]

hm, i can't see any comment-

[christosts]

my bad, the comment should be published now

[tzugen]

I have update the comments in case you didn't get a notice :)

[christosts]

Thanks! I merged the PR, with some changes and unit tests. It should appear here once we update the main branch