Include D standard library source with packaged releases?

[Jon Degenhardt]

I'm wondering if LDC packaged releases should include source for 
D standard libraries (druntime, phobos). This would enable the 
ldc-build-runtime tool to operate without downloading the library 
source for the release as a separate step.

A specific rationale for doing this would be to be friendlier to 
package mangers like HomeBrew that have an aversion to downloads 
during the build process. I don't know if other package managers 
have similar constraints, but it seems a reasonable restriction.

For the apps I tested, building with LTO against druntime/phobos 
proved so valuable that it is desirable to build with these 
settings. If other apps show similar results there will be 
increased value in enabling these build steps in package mangers.

--Jon