Update index.md (#5701)
Update index.md (#5701)

Fixed hyphenation (was an underscore).
Guneet-Dhillon/mxnet,Guneet-Dhillon/mxnet,Guneet-Dhillon/mxnet,Guneet-Dhillon/mxnet,Guneet-Dhillon/mxnet,Guneet-Dhillon/mxnet,Guneet-Dhillon/mxnet,Guneet-Dhillon/mxnet,Guneet-Dhillon/mxnet