update tomcat dependency fix for japanese/xgate.

• updated master_sites, distinfo, plist for new version
• drop dist_subdir (no longer required)
• use java 1.6+ (required)
• move to copyshare installation (to avoid security implications, everything can be 444)
• don't require jar for post-extract (use tar)

PR: ports/161230
Submitted by: Jason Helfman <jhelfman@e-e.com>
Approved by: maintainer timeout (14 days, and 22 days)