Add packages to Fedora 20 package list

Otherwise, you get this error:
``CMake Error at /usr/share/cmake/Modules/FindPackageHandleStandardArgs.cmake:108 (message):
  Could NOT find SDL (missing: SDL_LIBRARY) (found version "1.2.15")
Call Stack (most recent call first):
  /usr/share/cmake/Modules/FindPackageHandleStandardArgs.cmake:315 (_FPHSA_FAILURE_MESSAGE)
  /usr/share/cmake/Modules/FindSDL.cmake:176 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
  CMakeLists.txt:15 (find_package)``

or this one:
``fatal error: gnu/stubs-32.h: No such file or directory``