message: [examples/lang] Add wasm-prune (needed for now)
diff: PROJNAME=erc20
  -cargo clean
  -rm Cargo.lock
  +# cargo clean
  +# rm Cargo.lock
  CARGO_INCREMENTAL=0 cargo build --release --target=wasm32-unknown-unknown --verbose
  wasm2wat -o target/$PROJNAME.wat target/wasm32-unknown-unknown/release/$PROJNAME.wasm
  cat target/$PROJNAME.wat | sed "s/(import \"env\" \"memory\" (memory (;0;) 2))/(import \"env\" \"memory\" (memory (;0;) 2 16))/" > target/$PROJNAME-fixed.wat
  wat2wasm -o target/$PROJNAME.wasm target/$PROJNAME-fixed.wat
  wasm-opt -Oz target/$PROJNAME.wasm -o target/$PROJNAME-opt.wasm
  +wasm-prune --exports call,deploy target/$PROJNAME-opt.wasm target/$PROJNAME-pruned.wasm
  \ No newline at end of file
  