Refactoring 3rdparty build system

[metux]

Hi folks,
I'm currently working on refactoring the 3rdparty build scripts. The goals are:
* simpler structure/process with less code
* cleaner separation between packages
* individual packages can be built individually
* cleanup duplicate version definitions (eg. versions.def <->plat_common.def)
It's still quite incomplete and hackish, but feel free to play around:


repo: git@gitorious.org:open-zimbra/open-zimbra.git
branch: HACK_BUILD

cu