Remote transaction execution (#4684)

* return errors on database corruption

* fix tests, json tests

* fix remainder of build

* buffer flow -> request credits

* proving state backend

* generate transaction proofs from provider

* network messages for transaction proof

* transaction proof test

* test for transaction proof message

* fix call bug

* request transaction proofs from on_demand

* most of proved_execution rpc

* proved execution future

ethcore/src/lib.rs

@@ -79,7 +79,6 @@
 //!   cargo build --release
 //!   ```
 
-
 extern crate ethcore_io as io;
 extern crate rustc_serialize;
 extern crate crypto;
@@ -141,12 +140,12 @@ pub mod action_params;
 pub mod db;
 pub mod verification;
 pub mod state;
+pub mod env_info;
 #[macro_use] pub mod evm;
 
 mod cache_manager;
 mod blooms;
 mod basic_types;
-mod env_info;
 mod pod_account;
 mod state_db;
 mod account_db;