Add a port of the development version of DragonEgg.
DragonEgg is a gcc plugin that replaces GCC's optimizers and code
generators with those from the LLVM project. It works with gcc-4.5
or gcc-4.6, can target the x86-32/x86-64 and ARM processor families.
It fully supports Ada, C, C++ and Fortran. It has partial support
for Go, Java, Obj-C and Obj-C++.
Feature safe: yes