* Replace ethcore-logger with env-logger.
* Fix logger initialization in WASM tests.
* uncomment logger initialization in secret store
* Don't use ethcore-logger in whisper.
* Move ethcore-logger within parity dir.
* Uncomment rest from secret-store.
* Use `let _ =` in private_contract for consistency
* `ok()` to `let _ =` fix in service
* Use `let _ = ` for state_db
* 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
