Enhance nested TransCo pretty-printing
Nested TransCo were printed with a lot of indentation, e.g.:
`cast` (Sub (Sym (Foo.D:R:Index[0] <Bool>_N <'[]>_N)) ; ((Index
(Sym (SubDef (<1>_N,
<1>_N)))
<'[Bool]>_N)_R ; ...
With this patch we print them as follows:
`cast` (Sub (Sym (Foo.D:R:Index[0] <Bool>_N <'[]>_N))
; (Index (Sym (SubDef (<1>_N, <1>_N))) <'[Bool]>_N)_R
; Sub (Sym (Foo.D:R:Index[1] <1>_N <Int>_N <'[Bool]>_N))
; (Index (Sym (SubDef (<2>_N, <1>_N))) <'[Int, Bool]>_N)_R