* Decode patricia node with UntrustedRlp
(cherry picked from commit efb993b8e7ce087f092cb8c2f633c62ad87e4fb8)
* Replace Rlp with UntrustedRlp in triedbmut
* Handle node decode results in trie
* separate migration from util and make its dependencies into libs:
* snappy
* kvdb
* error
* common
* renamed common -> macros
* util error does not depend on snappy module
* ethsync does not depend on util nor ethcore_error
* nibbleslice and nibblevec merged with patricia_trie crate
* removed unused dependencies from util
* util journaldb traits does not need to be public
* util_error
* fixed ethcore compile error
* ignore .swo files
* Update chain.rs
