finalizeBundleIPFS not used/expensive

[truebitfoundation]

finalizeBundleIPFS not used/expensive

[mrsmkl]

1. The merkle root is just created from the code root and input roots (input data, input names, input sizes). wasm -m -input should generate that offline.

2. Perhaps easy to optimize by using lookup for empty subtrees.

[hswick]

@mrsmkl Can you take a look at this test and see what needs to be changed?

Currently this fails.

[mrsmkl]

I'll hopefully have time tomorrow to fix it. There are at least two issues:

1. the code file should only be added to the bundle when finalizeBundleIPFS is called
2. the root for the code should be the pre-processed code hash given by wasm -m -input (this is the root given by emscripten-module-wrapper)

[hswick]

Looks like the optimization reduced gas usage by 250000