Allow uploading of `bytes` or file-like objects from memory

Closes #10

See merge request !10

Adds the ability to upload any `bytes` or file-like objects (`open`, `BytesIO`) to whats-th.is, in the same way as any file on the file system like previously, through objects with properties `data` and `name`. An `owo.File` namedtuple is exposed to allow this to be easily done.

fix(async_owo.py): update for latest aiohttp

Closes #9

See merge request !9

The reason for the `aiohttp2` file existing is now redundant (https://github.com/aio-libs/aiohttp/pull/916 got merged), so migrated to use regular aiohttp `MultipartWriter`.

happy belated 2018

- make `requests` a requirement

Termux dev

Fixes #5