The rules are now as follows:
* In `import` statements, as mandated by the WHATWG specification,
the import specifier is always treated as a URL.
If it is a relative URL, it must start with either / or ./ or ../
* A script name passed to deno as a command line argument may be either
an absolute URL or a local path.
- If the name starts with a valid URI scheme followed by a colon, e.g.
'http:', 'https:', 'file:', 'foo+bar:', it always interpreted as a
URL (even if Deno doesn't support the indicated protocol).
- Otherwise, the script name is interpreted as a local path. The local
path may be relative, and operating system semantics determine how
it is resolved. Prefixing a relative path with ./ is not required.
