Update `license header` and `scripts` (#8666)

* 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

src/lib.rs

@@ -1,4 +1,4 @@
-// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// Copyright 2015-2018 Parity Technologies (UK) Ltd.
 // This file is part of Parity.
 
 // Parity is free software: you can redistribute it and/or modify
@@ -283,7 +283,6 @@ fn hash256aux<A: AsRef<[u8]>, B: AsRef<[u8]>>(input: &[(A, B)], pre_len: usize,
 	};
 }
 
-
 #[test]
 fn test_nibbles() {
 	let v = vec![0x31, 0x23, 0x45];
@@ -296,7 +295,6 @@ fn test_nibbles() {
 	assert_eq!(as_nibbles(&v), e);
 }
 
-
 #[cfg(test)]
 mod tests {
 	use super::{trie_root, shared_prefix_len, hex_prefix_encode};