[packager] Packaging with a JRE as installed fails codesign on OSX 10.9.5 or 10.10

So this is a testing corner case that is actually going to be the default user case. If you install the JRE from the installer on Mac OSX 10.9.5+ or 10.10.x and use that JRE as the runtime the codesign will fail. This is because codesign became stricted in 10.9.5+ and 10.10+. We violate the following rules:

* Plugin must provide an Info.plist. We skip it because it is a symlink when installed
* Plugin frameworks must be signed. The JRE auto-update installs the sparkle framework, which we don't sign.
* No unexpected unsigned files. We have a Disabled.plist and Enabled.plist in the same directory as Info.plist. Those dont get signed.