sqlite support

[seema84]

can you please add a sqlite support?

[phemmer]

I've created a PR over at #28 to add support for this.
I've also created a custom release on my fork with a build available: https://github.com/phemmer/ChestShopNotifier/releases/download/1.2.1-sqlite/ChestShopNotifier.jar

Just put the following in your config:

database:
  type: sqlite

[seema84]

Is sqlite now fully supported (also to convert the data from mysql to sqlite and vice versa)?
The description still says that only mysql is supported.

[Phoenix616]

Looks like the PR didn't update the readme and I missed that on the review, thanks for noting that! Conversion between storage types isn't supported though, please open a new issue if you need that as a feature.