Update OmniSharp downloads with working links
Update OmniSharp downloads with working links

OmniSharp/omnisharp-vscode,gregg-miskelly/omnisharp-vscode,OmniSharp/omnisharp-vscode,OmniSharp/omnisharp-vscode,gregg-miskelly/omnisharp-vscode,OmniSharp/omnisharp-vscode,OmniSharp/omnisharp-vscode,gregg-miskelly/omnisharp-vscode,gregg-miskelly/omnisharp-vscode