filter: replace spaces with dashes & allow dots

[GeopJr]

Searching for awesome crystal should return https://github.com/veelenga/awesome-crystal, however due to the current filter, it gets converted into awesomecrystal.

This PR replaces spaces with dashes.

This also follows the GitHub naming scheme:

carc.in: https://carc.in/#/r/9x3w

Also, same issue with jennifer.cr which gets converted to jennifercr and doesn't return the repo.

carc.in: https://carc.in/#/r/9x3x