Merge branch 'feature/doc_get-started' into 'master'

Merge branch 'feature/doc_get-started' into 'master'

doc: Getting Started guides

* [x] Redesign ReadTheDocs home page to cover the following sections:
  * Get Started (new  + revised contents, see below)
  * API Reference
  * H/W Reference
  * API Guides (former "What Else?")
  * Contribute
  * Resources

* [x] Convert "Getting Started" guides from PDF to RST, review and update
  * ESP32-DevKitC Getting Started Guide
  * ESP-WROVER-KIT Getting Started Guide

* [x] Review installation  manuals for Windows, Linux and MacOS

  * Separate "Standard / cookie cutter" contents from "Advanced / customize this installation" contents
  * Harmonize "Standard" installation instructions by providing distinct sections

      * (1) Install Prerequisites
      * (2) Install Toolchain (binary only)
      * (-) O/S flavors, ref to "Advanced" installation

* [x] Extract / update existing instructions common to all O/S - idf-template based
  * (3) Get esp-idf
  * (4) Start a Project
  * (5) Connect
  * (6) Build and Flash
  * (7) Monitor

* [x] Correct partition table address from 0x4000 to 0x8000 in `docs/get-started/make-project.rst` and `README.md`

See merge request !612