Fixes things like:
* exported type/method/function X should have comment or be unexported
* comment on exported type/method/function X should be of the form "X ..."
(with optional leading article)
Refs. #213.
* func to get private key from raw bytes
* added function to create raw transfer tx
* fixes
* more fixes
* prettify code and comments; neoscan interaction put in dedicated files
* block partial persist
* replaced refactored files with old one.
* removed gokit/log from deps
* Tweaks to not overburden remote nodes with getheaders/getblocks
* Changed Transporter interface to not take the server as argument due to a cause of race warning from the compiler
* started server test suite
* more test + return errors from message handlers
* removed --race from build
* Little improvements.
