v4.0.0 - Selected Cipher

Went full circle. Back to a pure collection of functions. Cipher is set to ECDH P-521 AES-256-CBC.

Features:

• initialization vector included in cipher, no manual iv generation needed anymore
• import and export encrypted private key pems

Breaking changes:

• all functions previously under utils are now toplevel exports
• no more Webcryptobox class, class methods moved to toplevel exports using preselected cipher
• derivePrivateKey has been renamed to getPrivateKey