Fixing another deadlock in trace db

Fix up the VM trace.

fixed parsing export params, fixes #1826

* Buffered DB

* Use identity hash for MemoryDB

* Various tweaks

* Delayed DB compression

* Reduce last_hashes cloning

* Keep state cache

* Updating tests

* Optimized to_big_int

* Fixing build with stable

* Safer code

* Bumping clippy

* Fixing clippy warnings

* Cargo.lock (latest nightly?)

* memorydb ub patch and other cleanup

* fix denote invocations

* move trie traits into trie module

* replace "denote" with shim

* triedb returns results and no longer panics

* fix warnings

* get ethcore compiling

* warn on trie errors in ethcore

* remove unsafety from node decoder

* restore broken denote behavior for this branch

* fix overlayrecent fallout

* fix triedb tests

* remove unwrap in state

* alter Trie::get to return Result<Option<_>>

* fix refcell error in require

* fix test warnings

* fix json tests

* whitespace

[ci:skip]

* Avoid unneeded match/indentation

* whitespace

* prettify map_or_else

* remove test warning

* Fixing account naming

* Using geth format for files. Avoid re-importing existing keys with different names.

* Adding expect for time format

* add inject to journaldb

* adjust docs

* add test; fix refcounteddb impl

* fewer panics, fail on invalid insertions or deletions

* fixed importing presale wallet with encseed longer than 96 bytes

* fixed incorrect pkcs unpadding in decrypting presale wallet

* Making ConfirmationsQueue a bit more generic [WiP]

* Generalizing cofirmations

* New confirmations types - tests

* Separating transaction type in queue. Closes #1310

* Handling sign requests

* Speeding up tests

* Renaming methods

* eth_postSign

* Bumping ui

* Development mode for Signer

* CLI option for signer-dev

* Renaming CLI option

* Make obvious that CLI option is insecure.

[ci:skip]

* Additional warning over security

* Mining fixes.

- Use queue to determine whether we're mining
- Kick stale hash rates

Fixes #1794
Fixes #1641

* Fix tests.

* Address grumbles.

* removed frombytes stuff

* removed jsonrpc handler from nano

DRYing build scripts

Allow code from spec json

* fix nano interface

* add nano tests to target