Update tests to support new call/create interface

[lrettig]

Cf. ewasm/evm2wasm#184, ewasm/design#70. This appears to be causing issues in ewasm/evm2wasm#196 as some of the vmTests there are failing like the below. AFAICT it's coming from https://github.com/ewasm/ewasm-kernel/blob/master/tests/interface/call.wast which needs to be updated.

# env1 env1
not ok 1076 should not have VM exception
  ---
    operator: fail
    at: checkResults (/Users/lanerettig/wip/eth/evm2wasm/tests/runVmTests.js:122:9)
    stack: |-
      Error: should not have VM exception
          at Test.assert [as _assert] (/Users/lanerettig/wip/eth/evm2wasm/node_modules/tape/lib/test.js:225:54)
          at Test.bound [as _assert] (/Users/lanerettig/wip/eth/evm2wasm/node_modules/tape/lib/test.js:77:32)
          at Test.fail (/Users/lanerettig/wip/eth/evm2wasm/node_modules/tape/lib/test.js:318:10)
          at Test.bound [as fail] (/Users/lanerettig/wip/eth/evm2wasm/node_modules/tape/lib/test.js:77:32)
          at checkResults (/Users/lanerettig/wip/eth/evm2wasm/tests/runVmTests.js:122:9)
          at runner (/Users/lanerettig/wip/eth/evm2wasm/tests/runVmTests.js:71:11)
          at <anonymous>
  ...
vmExceptionErr: LinkError: WebAssembly Instantiation: Import #16 module="ethereum" function="call" error: imported function does not match the expected type
    at VM.run (/Users/lanerettig/wip/eth/evm2wasm/node_modules/ewasm-kernel/vm.js:16:51)
    at Kernel.run (/Users/lanerettig/wip/eth/evm2wasm/node_modules/ewasm-kernel/index.js:35:20)
    at runner (/Users/lanerettig/wip/eth/evm2wasm/tests/runVmTests.js:67:29)
    at <anonymous>