SSL Button: Fix issues around printing Hash sums

- Use SHA 265 instead of obsolete MD5 where possible (Qt5)
- Remove <tt> formatting: that simply looked ugly
- Wrap SHA 265 hash
- Use spaces as separators

As usual, the default needs to remain ':' separation, because
it's needed to pass valid hashes to csync.
Fix dataLocation on Linux/BSD

From the Qt 5 documentation:

  Note: when porting QDesktopServices::DataLocation(obsolete)
        to QStandardPaths::DataLocation, a different path will
        be returned.

        QDesktopServices::DataLocation was GenericDataLocation
        + "/data/organization/application", while
        QStandardPaths::DataLocation is GenericDataLocation
        + "/organization/application".

We'll resort to the deprecated version, since we'll need to fix
data locations to be XDG compliant sooner than later anyway
(currently scheduled for 1.8)