sr3 relative path on modified downloads, wrong reposts in some cases.

[petersilva]

given subscriber settings like:

• prefix v03
• postBaseDir /A/B/C
• directory /A/B/C/D/E
• mirror off.

a file mine.txt obtained will be written to: /A/B/C/D/E/mine.txt

• topic: v03, and a relPath of "mine.txt"

This is fine for downloading, as it gets it written to the right place (and topic does not matter) but incorrect when re-posting for subscribers. The correct values would be:

• topic:v03.D.E relPath: D/E/mine.txt

Need to confirm that what the code does, and correct it. basically, mirror should affect download path, but the message should be correct relative to baseDir... not affected by relPath in download.

[petersilva]

This isn't covered in test suites because whenever we have mirror off, it isn't reposted.