Add Get Native Memory Info on ESP32

[AdrianSoundy]

Description

Allows the information about amount native memory to queried from Managed code
Using nanoFramework.Hardware.Esp32

Motivation and Context

To allow testing of memory leaks in unit tests

How Has This Been Tested?

Simple test app

Types of changes

• Improvement (non-breaking change that improves a feature, code or algorithm)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Config and build (change in the configuration and build system, has no impact on code or features)
• Dependencies (update dependencies and changes associated, has no impact on code or features)
• Unit Tests (work on Unit Tests, has no impact on code or features)
• Documentation (changes or updates in the documentation, has no impact on code or features)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[nfbot]

@AdrianSoundy there are issues with the code style on the source files.
A PR was submitted with the code style fixes. Please click https://github.com/AdrianSoundy/nf-interpreter/pull/40, review the changes if you want and merge it.

Make sure to follow the project code style. Check the details here on how it works and the tools required to help you with that.

[AdrianSoundy]

@josesimoes
I merged a change for this in nanoClr but this seems to be getting a build error on download logo.
Can you have a look whats happening. Maybe only temporary.