Make it easier to find Lazydocker's default config file

Each in a while (every few months) when I want to add a new custom command I struggle to remember where to find Lazydocker's config file. I have to go to Github and check the readme to find out.

**Enhancement Suggestion**
Instead of having the default config file in `~/.config/jesseduffield/lazydocker/` it would be easier to remember the location if it was in `~/.config/lazydocker/`

**Describe alternatives you've considered**
A workaround is to define a custom location during install. But that could lead to the problem that I forget my custom location and then even checking readme on Github wouldn't help :)