Allow any number of spaces in `abstract type` and `primitive type`

[jmert]

The regular expressions should accept more than a single space in abstract type and primitive type since they still parse correctly. I came across this in HDF5.jl where extra space was used to line up some names:

abstract  type Hmpih end
primitive type Hmpih32 <: Hmpih 32 end
primitive type Hmpih64 <: Hmpih 64 end

Before:

After:

[carlobaldassi]

Thanks!