Since the base URL and base path are user inputs, I'd like tkr to be resilient to any combination of leading and trailing slashes so people don't have to worry about that. This adds some helper functions to normalize URLs and adds tests to confirm that all combinations are handled correctly.
Reviewed-on: https://gitea.subcultureofone.org/greg/tkr/pulls/38
Co-authored-by: Greg Sarjeant <greg@subcultureofone.org>
Co-committed-by: Greg Sarjeant <greg@subcultureofone.org>
