ecdsa 0.15

tl;dr:

• much faster (around 20x)
• dedicated API for ECDH

Bug fixes:

• from curves import * will now correctly import BRAINPOOLP256r1 and
  BRAINPOOLP320r1 curves.

New features:

• ECDH operations have a public explicit API.
• Large hashes are now supported with small curves (e.g. SHA-256 can be used
  with NIST192p).
• VerifyingKey now supports the precompute() method to further speed up
  signature verification with the given instance of the key.

New API:

• VerifyingKey, SigningKey, Public_key, Private_key and
  CurveFp now have __eq__ methods.
• ecdsa.ecdh module and ECDH class.
• PointJacobi added.
• VerifyingKey.verify_digest, SigningKey.sign_digest and
  SigningKey.sign_digest_deterministic methods now accept allow_truncate
  argument to enable use of hashes larger than the curve order.
• VerifyingKey from_pem and from_der now accept hashfunc parameter
  like other from* methods.
• VerifyingKey has precompute method now.
• VerifyingKey.from_public_point may now not perform validation of public
  point when validate_point=False argument is passed to method.
• CurveFp constructor now accepts the h parameter - the cofactor of the
  elliptic curve, it's used for selection of algorithm of public point
  verification.

Performance:

• randrange now will now perform much fewer calls to system random number
  generator.
• PointJacobi introduced and used as the underlying implementation; speeds up
  the library by a factor of about 20.
• Library has now optional dependencies on gmpy and gmpy2. When they are
  available, the elliptic curve calculations will be about 3 times faster.

Maintenance:

• expected minimum version of six module (1.9.0) is now specified explicitly
  in setup.py and tested against.
• Significantly faster test suite execution.