Add Go version for heroku

[My6UoT9]

Heroku requires an extra line so it knows which go version to use.
https://github.com/heroku/heroku-buildpack-go#go-module-specifics

[fmartingr]

Hey @My6UoT9, thanks for the contribution! I'm merging this right away.

I may put a "Deploy to heroku" button in the readme as well, that still exists, right?

[My6UoT9]

I think it does yes, I am sorry I should have tested more extensively.
Sofar it seems I loose all data when heroku starts again, I have to check how to have data persisted.

[fmartingr]

I think it does yes, I am sorry I should have tested more extensively. Sofar it seems I loose all data when heroku starts again, I have to check how to have data persisted.

Yeah, I assume that using SQLite the database will be created on the dyno directly, which is ephemeral by default. If I recall correctly, in order to add heroku support properly an app.json needs to be created in the root of the repository. So far your change may be useful for people that want to take a quick peek at Shiori, they can deploy it to heroku and test it there even though a more permanent solution will require more work.

[My6UoT9]

Hm yes, maybe add a warning :)