Environment is now a struct (not an interface). This
reduces a lot of tech-debt throughout the codebase where a virtual
machine environment had to be implemented in order to test or run it.
The new environment is suitable to be used en the json tests, core
consensus and light client.
Support for legacy version 0.9.x is gone. The compiler version is no
longer cached. Compilation results (and the version) are read directly
from stdout using the --combined-json flag. As a workaround for
ethereum/solidity#651, source code is written to a temporary file before
compilation.
Integration of solc in package ethapi and cmd/abigen is now much simpler
because the compiler wrapper is no longer passed around as a pointer.
Fixes#2806, accidentally
Jeffrey Wilcke
Felix Lange
Zsolt Felfoldi
Péter Szilágyi