Preliminary fix for debug info generation with LLVM 3.4.

There is no debug information generated for several types.
As LLVM 3.4 does not support empty nodes, it is now time to
implement the missing debug info.
Merge pull request #450 from redstar/debuginfo

Preliminary fix for debug info generation with LLVM 3.4.
Ensure LLVM LDFLAGS are placed after libraries in build commands.
Merge pull request #452 from WebDrake/ldflags

Ensure LLVM LDFLAGS are placed after libraries in build commands.

Let's try this – add the removal of the second LLVM_LDFLAGS instance in the LDMD_EXE libraries if new LDMD linker errors pop up.
Yet another try