Fixup: PATH_SAFE

[digitalresistor]

This fixes PATH_SAFE to include more of the safe characters from RFC3986.

Closes #290

[mmerickel]

You left a few characters (like _) out according to Pylons/pyramid#2811. Any particular reason?

[digitalresistor]

Yes:

urllib.parse.quote:

Replace special characters in string using the %xx escape. Letters, digits, and the characters '_.-' are never quoted.

https://docs.python.org/3/library/urllib.parse.html#urllib.parse.quote

[mmerickel]

Great, thanks.

[mmerickel]

Can you add one more test for a url containing these characters to ensure they are no longer quoted? The added test appears to just check if [] is still quoted. It looks like you could just add to the test_path_quoting test directly above.

[digitalresistor]

Update the only existing test :P