* Update to substrate alpha.7
* Remove gas limit from contracts put code
* Rename SystemEvent::ReapedAccount to KilledAccount
* Log debug event received before attempting to decode
* Temporary registration of Balance type before #102 merged
* Show contract test errors, increase instantiate gas_limit
* Support custom clients.
* Simplify trait bounds.
* Plain and double map storage support.
* Simplify more trait bounds.
* Add proc macro.
* Add Call, Event and Store traits.
* Update proc-macros.
* Add with_system for proc-macro.
* proc-macro: test: support signature and extra fields.
* proc-macro: test: support sharing state accross steps.
* proc-macro: test: fetch state sequentially.
* Elide lifetimes.
* Add test for plain storage.
* Run rustfmt.
David Craven