Don't pin click dependency

Future upgrades are not expected to break functionality
Correct docs about shell option
Add speed option
Add speed as a command-line option as well
Who needs folders anyway?
Always add color to user and directory in prompt
Remove unnecesssary --check-output option

And fix bug with cwd in custom prompts
Bump dev version
This ain't gonna be stable
Bump version -> 0.2.0

and fix changelog date for 0.1.0