Image paths aren't relative to presented markdown file

[TymekDev]

Describe the bug
The paths provided in the images (and codio) inclusion statements ![](path/to/image) are treated as relative to current working directory and not to the markdown file location.

To Reproduce
This won't work (see the screenshot below):

pip install present
git clone https://github.com/vinayak-mehta/present
cd present

present examples/sample.md

This will work just fine:

cd examples
present sample.md

Expected behavior
I would expect present to work without having to change directory first.

Screenshots

Environment

• OS: Ubuntu 20.04.1 LTS
• Terminal emulator: kitty
• Python version: 3.8.2
• present version: 0.5.1

[vinayak-mehta]

Thanks for reporting this and opening a PR!