doc: juxtaposition does *not* work with variable coordinates.
formatting fixes
change BigInt and BigFloat .d field type to Ptr{Culong}.

This is the actual C type of this data, which makes these things a
bit easier to work with if you actually want to look at the data.
run in cygwin
Merge branch 'master' of https://github.com/JuliaLang/julia into appveyor