Use system cert store, not Java's

[tresf]

QZ Tray should inform Java to use the system's keystore so proxies don't cause print failures. On Windows and macOS this is possible through command line invocation.

Windows:

-Djavax.net.ssl.trustStoreType=Windows-ROOT
# or
-Djavax.net.ssl.trustStoreType=Windows-MY

macOS:

-Djavax.net.ssl.trustStoreType=KeychainStore

This may be best paired with #468