Handle trailing slashes in basename

[davis]

currently:

// this works
history = useBasename(createHistory)({
  basename: '/base/url'
})

// but this doesn't
history = useBasename(createHistory)({
  basename: '/base/url/'
})

this pr handles both cases

[taion]

Do we really need this in the code though? I feel like it'd be easier just to tell people to not put a trailing slash in basename.

[davis]

Intuitively I feel like if the basenames: '/' and '' have the same behavior than so should /base/ and /base

[mjackson]

I'd be ok with this change. There are failing tests that need to be fixed, though. Can you please fix them first, @davis?

[taion]

Test failure is not related to the PR I don't think - I'm re-running the build.

[taion]

Oh, never mind, I didn't scroll down far enough - those are real test failures.

[davis]

Hey guys, I've changed the code to use slice/charAt instead of startsWith/endsWith so that the tests pass in all environments.

[taion]

Thanks! Do we need to update any docs or changelogs to go with this?

[mjackson]

We can merge this for now, @taion. I'll add a "contributing" doc that explains how to update CHANGES.md when making PRs.

[mjackson]

Thanks @davis !