Fix incorrect network prefix in Java Meterpreter

Apparently, getNetworkPrefixLength can return -1, which confuses the Ruby
side. Therefore fall back to guessing the prefix in this case, as we do it
for Java <= 1.6.
Add bins for #1748
Land #1748, fix for java meterp network prefixes

[Closes #1748]
Add OSVDB ref to sap_configservlet_exec_noauth
Add safari webarchive uxss to framework as an aux module.
Merge #1767, @jvennix-r7's .webarchive UXSS

For disclosure details, see:

https://community.rapid7.com/community/metasploit/blog/2013/04/18/abusing-safaris-webarchive-file-format
Make sure xor encoders work with odd padding