Initial commit for SONiC PDE

[wbschwar]

Initial commit for SONiC PDE

[wbschwar]

• What I did
  This change introduces the PDE (platform development environment which is described here,
  Pde doc SONiC#407

The goal of the PDE is to provide a lightweight development environment for ODMs to quickly develop and test their platform plugins and validate necessary platform configuration files for proper SAI operation. Futhermore the PDE provides a pytest based suite to provide quick automated validation of platform plugins using JSON test and configuration data to describe the platform which is being tested.

• How I did it

PDE test code is located under src/sonic-platform-pdk-pde

Build infrastructure will be introduced in a pull request in sonic-buildimage

• How to verify it
  The PDE environment must first be enabled in rules/config (ENABLE_PDE=y) must be un-commented.
  Second, build target command is "make target/sonic-$MACHINE-pde.bin

• Description for the changelog
  Platform Development Environment (PDE): Lightweight platform development and test environment.

• A picture of a cute animal (not mandatory but encouraged)