The `patricia_trie` crate is generic over the hasher (by way of HashDB) and node encoding scheme. Adds a new `patricia_trie_ethereum` crate with concrete impls for Keccak/RLP.
* Update `add_license` script
* run script
* add `remove duplicate lines script` and run it
* Revert changes `English spaces`
* strip whitespaces
* Revert `GPL` in files with `apache/mit license`
* don't append `gpl license` in files with other lic
* Don't append `gpl header` in files with other lic.
* re-ran script
* include c and cpp files too
* remove duplicate header
* rebase nit
* 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
David
Marek Kotewicz
Niklas Adolfsson