Further refinements of lazygit config (eg keybindings)

[kieranpotts]

• https://github.com/jesseduffield/lazygit/blob/master/docs/Config.md
• https://github.com/jesseduffield/lazygit/blob/master/docs/Custom_Command_Keybindings.md

Note: custom paging within lazygit is not supported on Windows

[kieranpotts]

Moved to workspaces repo.