Remove hardcoded path to howdoi

[joshjordan]

This breaks on any machine that doesn't keep howdoi in /usr/local/bin, which seems like an unreasonable assumption to make. On my machine, howdoi was installed to /usr/local/share/python. To make matters worse, no indication is given that howdoi couldn't be found - it just deletes the text on the current line. There are probably plenty of people who tried this out and decided it just didn't work even though they have howdoi installed properly.

Why not just remove the path_prefix functionality and require that howdoi be on your system path?

[amitness]

I'm working on a fork of this project: https://github.com/amitness/subflow in which I'm planning to add more functionalities since this repo hasn't been updated for a long time. The issue is fixed there.