Jar should not be packed with gems/cache/*.gem

[rtyler]

Right now the cache/ directory contents are being included in the packaged up jar file, but serve 100% no purpose other than to bloat the size of the package.

In one case internal to Lookout, the cache/ directory for a jar-based project is 14MB all on its own!

[rtyler]

One temporary work-around is to use:

jrubyJar {
   exclude '**/*.gem'
}

[mkristian]

+1