Add a way to manually configure labels

[franchioping]

As described in #6, regex snippets show up as their expression, adding a lot of bloat to the completion menu
With this pull request, you can manually edit the label through the config, like this

          { name = 'luasnip', opts = { label_aliases = {
            ['(?<!\\\\)(sec)'] = 'sec',
          } } },

And now, the snippet will show up as 'sec', but still match as '(?<!\\\\)(sec)'

Working example below (list of snippets on the right, has nothing to do with the plugin configuration)

[bew]

Instead of having to configure the completion source, I think ot would be much nicer to add a label to each snippet that needs a custom one. This way at least you don't have to duplicate the trigger

[saadparwaiz1]

I agree with @bew here. I don't think this change should go in as that'll mean duplicating your snippet in two places. LuaSnip and then cmp_luasnip

[franchioping]

Im not increadibly familiar with luasnips, so im not sure how it would be structured/if it would need some new feature, but I do agree this isn't optimal, and more like a patched-on fix
I'll look into how the configuration would be through luasnips

[franchioping]

Is a function that takes a snippet and an alias as an input and returns the snippet a viable solution? so a snippet file would look something like this.

return {
  aliasfunc(s(<configure snippet here>), "alias")
}

the function would add the alias, in the same format as previously suggested, and simply return the snippet so it can still be used like normal.