minified resources for plone static

@bloodbare i've created a minified version of plone-compiled.js:
plone-compiled.min.js and a source map file plone-compiled.min.js.map and included both in this pull-request, together wich some js config.

I created with the changed generate_gruntfile.py script from this commit: https://github.com/plone/buildout.coredev/commit/4d1936b71a1293672ce92155788442e056797772

@bloodbare are you ok with these changes? otherwise i'll revert the generate_gruntfile.py changes.
the only thing is, source maps seem not to work....