Snippets repo is gone and some snippets don't work

I have installed the snippets plugin from within Micro, but found that the PHP snippets doesn't work. So I looked for the repo via the repo.json file and discovered that it is no longer on Github: https://github.com/tommyshem/micro-snippets-plugin

I think it would be much better to move the snippets feature to core since it is such a useful feature.

Regarding the PHP specifics, then I have looked at the source (it's from Vim) and it has a lot of snippets, but none is working.

Unknown snippet "if"
Unknown snippet "for"
Unknown snippet "foreach"
Unknown snippet "switch"

I have the same PHP snippet on Vim where it is working.

The file is also detected as PHP as it says ft:php.

Start with the snippets plugin entry in repo.json and verify whether the referenced GitHub repository is still available. Then inspect the PHP snippets sourced from Vim and reproduce the listed Unknown snippet errors; the issue is done when the PHP file is detected as PHP and the reported snippets work.