Major updates for usability

[Neo-Desktop]

Hi there - I did a bit of an overhaul of the code.

I intended to use this in my Discord Bot, but I couldn't import the generator without it having a copy of emojis.json in the current directory during runtime.

I initially made changes to compile in the database to avoid the runtime requirement.

These changes do break compatibility (I eliminated the config structure during my changes) so please use/merge this at your discretion.

If you do decide to merge this (and after any other changes are made) please feel free to add a tag noting a release version (i.e. v1.0.0) for go module versioning purposes

I will be maintaining my fork of this branch over at NeoDesktop/emojipasta

Thanks for the beautiful groundwork - I figured it's only fair to contribute back to the source repo :)

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Changelog:

Use edb.prebuilt.json from emojibot2
Provide example usage
Update readme to reflect changes
Simplify code/directory structure

new file:   .gitignore
modified:   Emojipasta.go
modified:   README.md
deleted:    assets/emojis.json
new file:   edb.prebuilt.json
new file:   example/main.go
deleted:    generator/generator.go