Most of this change is to boilerplate commentary such as license URLs.
This change was prompted by ftp://ftp.gnu.org's going-away party,
planned for November. Change these FTP URLs to https://ftp.gnu.org
instead. Make similar changes for URLs to other organizations moving
away from FTP. Also, change HTTP to HTTPS for URLs to gnu.org and
fsf.org when this works, as this will further help defend against
man-in-the-middle attacks (for this part I omitted the MS-DOS and
MS-Windows sources and the test tarballs to keep the workload down).
HTTPS is not fully working to lists.gnu.org so I left those URLs alone
for now.
* lisp/url/url-util.el (url-encode-url): Simplify.
url-generic-parse-url copes with multibyte strings just fine
(https://debbugs.gnu.org/cgi/bugreport.cgi?bug=24117#185).
* test/lisp/url/url-parse-tests.el
(url-generic-parse-url/multibyte-host-and-path): New test.
* test/lisp/url/url-parse-tests.el: Add tests covering url-generic-parse-url.
* test/lisp/url/url-expand-tests.el: Add tests covering url-expand-file-name.
* lisp/url/url-parse.el (url-generic-parse-url): Keep empty fragment
information in URL-struct.
* lisp/url/url-parse.el (url-path-and-query): Do not artificially turn empty
path and query into nil path and query, respectively.
* lisp/url/url-expand.el (url-expander-remove-relative-links): Do not turn
empty path into an absolute ("/") path.
* lisp/url/url-expand.el (url-expand-file-name): Properly resolve
fragment-only URIs. Do not just return them unchanged.
* lisp/url/url-expand.el (url-default-expander): An empty path in the relative
reference URI should not drop the last segment.