Update project zeroclipboard to v2.1.5

libgrabber updated project zeroclipboard to v2.1.5.

@zeroclipboard

### Metadata information

```json
{
  "metadata": {
    "packageManager": "github",
    "name": "zeroclipboard",
    "repo": "zeroclipboard/ZeroClipboard",
    "files": {
      "basePath": "dist/",
      "include": ["ZeroClipboard.Core.min.js", "ZeroClipboard.Core.min.map", "ZeroClipboard.js", "ZeroClipboard.min.js", "ZeroClipboard.min.map", "ZeroClipboard.swf"],
      "exclude": []
    },
    "path": "/home/jsdelivr/files/zeroclipboard",
    "localVersions": ["1.1.7", "1.2.2", "1.2.3", "1.3.3", "1.3.5", "2.1.1", "2.1.2", "2.1.3"],
    "remoteVersions": ["v1.2.0-beta.2", "v1.2.0-beta.3", "v1.2.1", "v1.2.2", "v1.2.3", "v1.3.0-beta.1", "v1.3.0", "v1.3.1", "v1.3.2", "v1.3.3", "v1.3.4", "v1.3.5", "v2.0.0-beta.1", "v2.0.0-beta.2", "v2.0.0-beta.3", "v2.0.0-beta.4", "v2.0.0-beta.5", "v2.0.0-beta.6", "v2.0.0-beta.7", "v2.0.0-beta.8", "v2.0.0", "v2.0.1", "v2.0.2", "v2.0.3", "v2.1.0", "v2.1.1", "v2.1.2", "v2.1.3", "v2.1.4", "v2.1.5"],
    "branchVersions": []
  },
  "version": "v2.1.5",
  "updated": true,
  "updatePath": "/home/jsdelivr/files/zeroclipboard/2.1.5",
  "branch": "zeroclipboard/v2.1.5"
}
```