Add Esperanto translation

[HappyHippo77]

This is my first time contributing to a project, so forgive me if I've made any mistakes. I followed the instructions in CONTRIBUTING.md for adding a translation language, hopefully I've done everything correctly.

I don't know how many people would be interested in translating this into Esperanto, but given it's a relatively small task I should be able to handle most of it by myself. Although there are no monolingual speakers of Esperanto (except for very young children raised by parents who only share Esperanto as a language, which is relatively uncommon), there is a small minority of individuals that prefer to use it on their computers, mainly students seeking to immerse themselves in the language more fully. As a student of the language myself, I've been searching for a translation project for some time, but all of my requests to add the language to existing projects have been rejected or ignored. Given the significant day-to-day usefulness of this app, I feel that an Esperanto translation may be appreciated by at least a small group of people.

I have not yet translated any of the strings, as I would prefer to do this via Weblate.