More efficient if

[mitschabaude]

• defer bindings import to initialize call
• make local blockchain async and call initialize
• change local blockchain usage in examples
• guard uses of Snarky and Pickles bindings by initialize call
• refactor to avoid bindings call
• make ml Test module an async function
• fix proof and cjs examples
• wasm js wrapper is only created on initialize
• export initialize and tweak import benchmarks
• changelog
• call initialize up front in benchmarks
• move sync runners behind an async function
• more changelog
• fix token test
• fix encryption example
• remove "main" export which confused webpack
• separate if implementation when one input is constant - promising but not perfect