Add Gotify-Ext

[StewartThomson]

Hi, I've created a gotify chrome extension for viewing and managing gotify server(s). It's available at https://chrome.google.com/webstore/detail/gotify/defcailckfpgaigaiijligpnjipkhhmg

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  - [StewartThomson/Gotify-Ext](https://github.com/StewartThomson/Gotify-Ext) A Browser extension for viewing and managing gotify servers

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