Installation step was added for runtime only (luvit and luvit/bundle). Files from lib/*.lua
were ignored intentionally.

There is example how to use CMake to build and install luvit with clang:
   mkdir -p build/install
   mkdir -p build/cmake && cd build/cmake
   CC=clang CXX=clang++ cmake -DCMAKE_INSTALL_PREFIX=../install -DCMAKE_BUILD_TYPE=Release ../..
   make install/strip