Stock-indicators

Added indicators:
- Average Directional Index (ADX)
- Average True Range (ATR)
- Commodity Channel Index (CCI)
- Correlation Coefficient
- Stochastic RSI

Chores:
- Index for history starts from 1 instead of 0

This is the initial release of **Stock Indicators for Python**, a Python wrapper of the Stock Indicators for .NET library.

Please treat all versions before 1.0.0 as previews. **Expect breaking changes as we get more [community feedback](https://github.com/DaveSkender/Stock.Indicators.Python/issues) and fine-tune everything.** We will enumerate breaking changes in these release notes.

For more information, see the:

- [documentation site](https://daveskender.github.io/Stock.Indicators.Python/)
- [PyPI project page](https://pypi.org/project/stock-indicators/)

Our priorities going forward are to:

1. add the other 60+ indicators from [Stock Indicators for .NET](https://daveskender.github.io/Stock.Indicators/).
2. work on performance tuning to improve library speed

This initial release includes 18 indicators:

- Aroon
- Average Directional Index (ADX)
- Moving Average Convergence/Divergence (MACD)
- SuperTrend
- Williams Alligator
- Bollinger Bands®
- Awesome Oscillator
- KDJ Index
- Relative Strength Index
- Stochastic Oscillator
- Stochastic RSI
- Williams Fractal
- Accumulation/Distribution Line (ADL)
- Arnaud Legoux Moving Average (ALMA)
- Exponential Moving Average (EMA)
- Simple Moving Average (SMA)
- Average True Range (ATR)
- Beta Coefficient

Special thanks to our lead maintainer LeeDongGeon1996 for all the hard work to get us here.

- update of documentation only

- remove unneeded target frameworks

This software library is published and available in the NuGet repository as [Skender.Stock.Indicators](https://www.nuget.org/packages/Skender.Stock.Indicators).

Changes in this release are mostly for internal development of the library:

- Skender.Stock.Indicators name used consistently for namespace, package, and DLL file (3)
- added VSCode settings (contributors to this package can use either VS Code or regular VS)
- added automatic Semantic Versioning in the build process (6)
- removed `internal set` on properties of public classes so end users can extend them in their own code (5)
- updated documentation

As a pre-release edition, you can expect that additional versions, even minor and patch versions, may contain breaking changes. Use with caution. We will mark the first fully stable version as 1.0.0 when it is ready for general use.

This initial package contains the following indicators:

- Simple Moving Average
- Exponential Moving Average
- Moving Average Convergence/Divergence (MACD)
- Relative Strength Index (RSI)
- Stochastic Oscillator
- Heikin-Ashi
- Bollinger Bands
- Ulcer Index
- Parabolic SAR

This software library is published and available in the NuGet repository as [Skender.Stock.Indicators](https://www.nuget.org/packages/Skender.Stock.Indicators).

As a pre-release edition, you can expect that additional versions, even minor and patch versions, may contain breaking changes. Use with caution. We will mark the first fully stable version as 1.0.0 when it is ready for general use.