Provide zipped javadoc archive from make

[Jiri Vanek]

Hello!

Firs, sorry for spamming three lists but imho it is really touching all of them - it will be change 
in makefile, and it is new feature for old docs....


Currently, when you run make all, javadoc is generated as directory. I do not wont to touch this. 
However, I would like to add target, which will pack generated javadoc... Lets say correctly to zip 
archive.

Having javadoc as directory have its advantages, but having javadoc as archive have another set of 
advantages. (eg main user of javadoc are IDEs. and all IDEs I know support archived javadocs. All 
library javadocs distributed over  web are distributed as zips, and they are not expected to be 
unpacked. Many tools crate archved javadocs by default and so on...)

I'm packaging openjdk for fedora, and next to java-1.X.0-openjdk-javadoc, and I wonted to provide 
java-1.X.0-openjdk-javadoc-zip so users have an choice to select zipped/unzipped javadoc depending 
on theirs usage. You may argue that size do not meter, but having four (6,7,8,9) jdks on machine, 
and so having 4 javadocs - it metres if it is 4x250mb or 4x50mb.

Also, when I was preparing this simple patch to my packages, I realised - am I compressing all? Am I 
compressing it correctly and in best way? Is delivering of *JDK's* javadoc as archive even safe?

So I would say that having this supported in upstream is much better then just pack zip it in 
distribution packages.

What do you think?

If you are interested, I will elaborate patch for jdk9 with wish for jdk8. Change should be simple, 
and the benefits worthy.

Thanx!
  J.