Merge branch 'ramfs-recipe' into 'master'

Add the ramfs recipe

See merge request redox-os/cookbook!235

recipes/kernel/recipe.sh

 GIT=https://gitlab.redox-os.org/redox-os/kernel.git
-BUILD_DEPENDS=(drivers init nulld randd redoxfs zerod)
+BUILD_DEPENDS=(drivers init nulld ramfs randd redoxfs zerod)
 
 function recipe_build {
     export INITFS_FOLDER="$(realpath ../sysroot)"

recipes/ramfs/recipe.sh

+GIT=https://gitlab.redox-os.org/redox-os/ramfs.git