Docs: cross-ref performance tips
Docs: cross-ref variables-and-scoping
Docs: cross-ref types chapter
Docs: cross-ref style guide
Docs: cross-ref strings chapter
Docs: cross-ref shelling out chapter
Docs: cross-ref metaprogramming chapter
Docs: cross-ref mathematical ops chapter
Docs: cross-ref numbers chapter
Docs: cross-ref functions chapter
Docs: cross-ref FAQ

Also fix Markdown syntax in blog post link.