Blackscholes

Support for greeks of binary options

**Full Changelog**: https://github.com/CarloLepelaars/blackscholes/compare/v0.1.7...v0.1.8

What's Changed
* BinaryCall and BinaryPut by CarloLepelaars in https://github.com/CarloLepelaars/blackscholes/pull/16

**Full Changelog**: https://github.com/CarloLepelaars/blackscholes/compare/v0.1.6...v0.1.7

What's Changed
* Add Calendar call and put spread by CarloLepelaars in https://github.com/CarloLepelaars/blackscholes/pull/15


**Full Changelog**: https://github.com/CarloLepelaars/blackscholes/compare/v0.1.5...v0.1.6

Add `alpha` greek, also called "gamma rent". This is the ratio between theta and gamma. This concept is explained in depth in Nassim Taleb's "Dynamic Hedging" p. 178-181.

**Full Changelog**: https://github.com/CarloLepelaars/blackscholes/compare/v0.1.4...v0.1.5

**Full Changelog**: https://github.com/CarloLepelaars/blackscholes/compare/v0.1.3...v0.1.4

- Bull and bear spread.
- Long and short Iron Butterfly
- More copyable code examples.
- Consistent type hints.
- Clearer documentation.

**Full Changelog**: https://github.com/CarloLepelaars/blackscholes/compare/v0.1.1...v0.1.2