update to the docs

[ryestew]

Filip was trying to use the plugin and it looked like he needed an ordered list describing what to do. This would be to replace this section's text: How to generate documentation.

1. Compile a smart contract
2. Go to the EthDoc Generator in the side panel and click the button to generate the docs.
3. The generated doc does NOT automatically get the focus in the Editor so click the EthDoc Viewer tab in Remix's Editor.