Fix parsing of URIs that have been URL encoded

This attempts to fix the following cases where the schemeless regexp will parse incorrectly parse the following if the parsed URI is encoded within another:

%2ftwitter.com
%3dyoutu.be
%252Fwww.fastcompany.com

For reference:

| Encoded | Actual | Notes |
|-------|-----|---------------------|
| %25 | % | Checked before 2F or 3D as it will appear if the URI is incorrectly double encoded |
| %2F | /  | e.g. http:// |
| %3D | = | this would appear in URIs like https://www.youtube.com/watch?v=w2zlW0O4nig&feature=youtu.be |