Remove Specialization in favour of generic typedef

src/bindgen/bindings.rs

src/bindgen/builder.rs

src/bindgen/ir/constant.rs

src/bindgen/ir/enumeration.rs

src/bindgen/ir/global.rs

src/bindgen/ir/item.rs

src/bindgen/ir/mod.rs

src/bindgen/ir/opaque.rs

src/bindgen/ir/specialization.rs

src/bindgen/ir/structure.rs

src/bindgen/ir/ty.rs

src/bindgen/ir/typedef.rs

src/bindgen/ir/union.rs

src/bindgen/library.rs

src/bindgen/monomorph.rs

src/bindgen/parser.rs

tests/expectations/alias.cpp

tests/expectations/cdecl.cpp

tests/expectations/euclid.c

tests/expectations/euclid.cpp