Clean up _parse_uri_s3x function, resolve edge cases

[mpenkov]

Fix #195

[menshikh-iv]

Looks good @mpenkov!

Can you also fix README.md please, goal - avoid misunderstanding.

[menshikh-iv]

@mpenkov 🔥

[piskvorky]

Strong -1 on the README changes. 1234 tells me nothing as a reader, port better. A person who doesn't understand that host, port, secret or user are placeholders is not going to be helped by seeing 1234 (in fact, probably even more confused, since they'll just type 1234 verbatim).

It's also inconsistent with keeping the rest as placeholders (host, user, secret…). Why is one concrete and the other general? Should we replace them all by a concrete "mock" value?

[mpenkov]

@piskvorky The problem with specifying host:port as an example is that it causes misunderstandings like #195. People try the examples verbatim and become surprised when things don't work.

I can see your side of the argument too, however. What's the best way to deal with this? Should we just add text that makes it obvious that strings like host, port, etc. are placeholders and need to be replaced with actual values?

[piskvorky]

Nah. Our audience here is technical. In my experience, a person who thinks host:port should be taken literally won't really be reading or understanding such additional texts anyway. And they'll definitely copy-paste 1234 too, so that still doesn't help.