Improve dispose Perf.

Merge pull request #65 from faustodavid/CreateFormatterForUtf8Json

Create resolver and formatter for Utf8Json

Add method EnsureCapacity

Indicating the capacity helps to avoid performance degradation produced by auto-growing

Improve AddRange perf.

Changelog:

• Performance enhancement in the method AddRange(T[] items) for ListPool and ValueListPool
• ValueListPool now can be created with parameterless constructor

Improve AddRange perf.

Changelog:
* Performance enhancement in the method AddRange(T[] items) for ListPool and ValueListPool
* ValueListPool now can be created with parameterless constructor

Add support for netstandard2_0

By adding support to NetStandard2_0, we can target more frameworks and work with the applications that haven't been migrated to dotnet core 3.0 or above.

At the moment we are targeting NetStandard2_1 and NetStandard2_0.

ListPool supports Span<T> and ReadOnly<T> from constructor

Now ListPool supports Span and ReadOnly from the constructor and from extensions methods. Additionally, create ListPool from an array was optimized.

ValueListPool support for stackalloc

Now ValueListPool is a ref struct with support for span as a buffer.

Performance improvements

Overall performance improvement for ListPool and ValueListPool

Span and Memory Support

Changelog:
* Improve performance of ValueListPool by removing buffer checks. Now is required to avoid parameterless constructor for ValueListPool.
* Add support for span and memory
* Add method AddRange

  ListPool is the general use of the implementation. ValueListPool is the zero heap allocations implementation. Note, because it is a struct it is passed by value, not by reference.

Rename ListPoolValue to ValueListPool

Changelog:
* Rename ListPoolValue to ValueListPool

ListPool is the general use of the implementation. ValueListPool is the zero heap allocations implementation. Note, because it is a struct it is passed by value, not by reference.