Void type is not shown correctly

[melonedo]

Currently, void is shown as CLFirstType, which is not very informative, this is because Clang includes First* and Last* as auxiliary enums that indicate ranges after main enum section, while the more informative one come first, changing the type mapping to prefer names that come first rather than last may solve this.

[Gnimuc]

A possible fix would be to filter out those marker enum names in https://github.com/JuliaInterop/Clang.jl/blob/master/src/cltypes.jl.