Increase java stack size to prevent StackOverflowError on optimize with jszip-maven-plugin

[kreyssel]

I use maven with the java default size settings.

If I now runs the optimization task with the jszip-maven-plugin, i get a StackOverflowError. After increasing the java stack size (-Xss) i can optimize my files without errors.

see https://groups.google.com/forum/?fromgroups=#!topic/requirejs/IqL7wuYs-AM

Would recommend to add this in README.

[stephenc]

Do you want to take a stab at improving the README?