v0.11

• Replaced parity-hash with fixed-hash (version 0.3.0-beta)
• Address no longer is a H160 type but has one internally.
  • It is possible to extract the inner H160 of an Address
• Now provides the U256 type via the uint crate (version 0.5.0-beta)
  • Also provides conversions between H256 and U256 types
• Updated rust-toolchain from 2018-07-24 to 2018-10-30
• Now propagates byteorder/std feature upon enabling std crate feature
• Fixed some minor warnings due to new compiler versions.
• Added a test feature for testing the crate.
• Updated the README for the new crate features.