Julia (Solidity IR) specification / interpreter

[mrsmkl]

Most of the builtins are not yet implemented, but they should be quite straightforward. I'll write some examples next, and then I'll start working on the compiler.

Also has a fix in block.lem for returning 0 when contract creation fails.

[pirapira]

Maybe it's a good idea to add some tests to .travis.yml file so that nobody can accidentally break the tests while changing something seemingly remote.

[pirapira]

Finally!