s2wasm no longer a thing

[jakibaki]

It was removed from binaryen but is still needed by the examples. WebAssembly/binaryen#1607

[jakibaki]

When trying to use the updated tutorial (wasmception) I get it to compile but when I try to run it it fails with
Parser error: src/vmir_wasm_parser.c:361 : Resizable table not supported