Valid scheme produces Validation Error

[fili]

e.g.
ssh+git@github.com:kvesteri/validators.git#egg=validators
mailto:example@example.com

See also:

• https://tools.ietf.org/html/rfc3986.html#section-3.1
• https://tools.ietf.org/html/rfc3986.html#section-1.1.2
• https://tools.ietf.org/html/rfc2368.html

[kvesteri]

PRs welcome 👍

[yozachar]

related #40 #55 | ref #241