Squashed 'libs/luajit-2.0-ironbee/' changes from b3c7f12..97122bf


git-subtree-dir: libs/luajit-2.0-ironbee
git-subtree-split: 97122bfc25eafe39674ce3beb1298a9f64a635f4
luajit: Sync with luajit-2.0/v2.0.1-fixed.
luajit: Reapply ironbee luajit build changes.
git: Remove luajit from being ignored by git.
docs: Update DEVELOPMENT with luajit changes.
docs: Make DEVELOPMENT markdown compatible.
Update luajit to 2.0.1.