Feature request: Generate `.remixicon` collection from SVG files
**Is your feature request about our website? Please describe.**

If you lost the `.remixicon` collection file, you must select each icon one by one again. So I just want to know if we can add a way to generate `.remixicon` collection from SVG files.

**Describe the solution you'd like**

```html
<input type="file" id="files" accept="image/svg" multiple />

<script>
function handleFileChange(event) {
  const files = event.target.files
  const svgs = Array.from(files).map(file => (file.name.replace(/\.svg$/, '')))

  if (svgs.length > 0) {
    const blob = new Blob([svgs.join(',')], { type : 'text/plain' })
    const fileName = `Remixicon_Collection_${Date.now()}.remixicon`
    const link = document.createElement('a')
    link.href = window.URL.createObjectURL(blob)
    link.download = fileName
    link.click()
    window.URL.revokeObjectURL(link.href)
  }
}

document.getElementById('files').addEventListener('change', handleFileChange, false)
</script>
```
