feat: Add option to always include cwd prefix

[tmccombs]

Fixes: #1243 Fixes: #1331

• [x] add test
• [ ] update changelog

[tavianator]

Not sure if this was mentioned in the linked issues, but it is already possible to get the leading ./ by specifying . as the search path explicitly, e.g.

$ fd . .
./cli.rs
./config.rs
...
$ fd --search-path .
./cli.rs
./config.rs
...

[sharkdp]

Thank you for the update