[pwstorage] Fix Windows UTF problems

[zisoft]

fixes #16603

This windows stuff is driving me nuts 🙂

• fix windows utf problems
• allow multiple servers for piwigo
• code formatting

Thanks to @XavierP56 for testing

[kmilos]

Note to self: will need to revisit when merging #15899

[zisoft]

@kmilos: Using UTF-8 locale in general would be great.
I first tried to use the generic Windows functions (CreadWrite instead of CreadWriteA etc.) to let Windows decide automatically but that leads to unreadable entries in the Windows Credential manager: #16603 (comment)

[kmilos]

I first tried to use the generic Windows functions (CreadWrite instead of CreadWriteA etc.) to let Windows decide automatically

It doesn't do anything automatically, one needs to explicitly convert to/from wchar_t/wstring UCS (UTF-16) to UTF-8 char/string...

[TurboGit]

Thanks!