ZipEncodingHelper calls System.getProperty("file.encoding"); should use Charset.defaultCharset()

ZipEncodingHelper calls System.getProperty("file.encoding")
However this can fail with a security exception.

It should use Charset.defaultCharset() instead.
This method also uses System.getProperty but does so as part of a doPrivileged block.
AIUI this will be done in the protection domain of the JVM classes rather than the domain in which the Compress code runs, so should be less likely to fail.