add initial GetStarted doc

GetStarted.md

+# Example soclabs Arm-Cortex-M0-based microcontroller project
+
+
+Recommended directory structure
+
+A good starting point for a template for building a Cortex-M based microntroller is to use the AAA components:
+
+Create a directory of (Read-only) Arm IP bundles from Product Download Hub, logged in with AAA credentials:
+
+Download Corstone-101:
+  https://developer.arm.com/downloads/view/BP306-GRP
+Download Cortex-M0 CPU:
+  https://developer.arm.com/downloads/view/AT510-GRP
+Download Micro-DMA PL230:
+  https://developer.arm.com/downloads/view/PL230-GRP
+
+and in each case
+  gunzip the <bundle>.tar.gz
+  gtar xfv <bundle>.tar
+
+The project is structured to work alongside IP provided under the Arm Acacdemic Access enttilements.
+
+Provide a soft-link to the downloaded and configured IP in a directory '**arm-AAA-ip**':
+
+```
+arm-AAA-ip --> link to directory of unpacked Arm IP directory trees
+|-- Cortex-M0
+|-- Corstone-101_Foundation_IP
+|-- DMA230_MicroDMA_Controller
+soclabs-cortexm0-mcu
+|-- ...
+```
+
+
+The Arm documentation can be referenced from the download trees:
+
+Cortex-M0 release note, and reference manuals:
+'''
+   arm-AAA-ip/Cortex-M0/*.pdf
+   arm-AAA-ip/Cortex-M0/AT510-BU-00000-r0p0-03rel3/doc/*.pdf
+'''   
+Corstone-101 release notes, and reference manuals:
+'''
+   arm-AAA-ip/Corstone-101_Foundation_IP/*.pdf
+   arm-AAA-ip/Corstone-101_Foundation_IP/BP210-BU-00000-r1p1-00rel0/documentation/*.pdf
+'''   
+PL230 MicroDMA release notes, and reference manuals:
+'''
+   arm-AAA-ip/DMA-230_MicroDMA_Controller/*.pdf
+   arm-AAA-ip/DMA-230_MicroDMA_Controller/PL230-BU-00000-r0p0-02rel1/*.pdf
+'''   
+
+The microcontroller simulation hierarchy is delivered in the '**soclabs-cortexm0-mcu**' directory:
+
+```
+soclabs-cortexm0-mcu
+|-- Cortex-M0
+|   |-- soclabs_demo
+|   |   software
+|   |   |   cmsis
+|   |   |   |-- CMSIS
+|   |   |   |   |-- Include
+|   |   |   |-- Device
+|   |   |   |   |-- ARM
+|   |   |   |   |   |-- CMSDK_CM0
+|   |   |   |   |   |   |-- Include
+|   |   |   |   |   |   |   |-- Source
+|   |   |   |   |   |   |   |--  ARM
+|   |   |   |   |   |   |   |--  GCC
+|   |   |   common
+|   |   |   |-- bootloader
+|   |   |   |-- debug_tests
+|   |   |   |-- demos
+|   |   |   |-- dhry
+|   |   |   |-- retarget
+|   |   |   |-- romtable_tests
+|   |   |   |-- scripts
+|   |   |   |-- validation
+|   |   |   debug_tester
+|   |   systems
+|   |   |-- cortex_m0_cpu
+|   |   |   |-- rtl_sim
+|   |   |   |   testcodes
+|   |   |   |   |-- apb_mux_tests
+|   |   |   |   |-- bitband_tests
+|   |   |   |   |-- bootloader
+|   |   |   |   |-- debug_tests
+|   |   |   |   |-- default_slaves_tests
+|   |   |   |   |-- dhry
+|   |   |   |   |-- dma_tests
+|   |   |   |   |-- dualtimer_demo
+|   |   |   |   |-- generic
+|   |   |   |   |-- gpio_driver_tests
+|   |   |   |   |-- gpo_tests
+|   |   |   |   |-- hello
+|   |   |   |   |-- interrupt_demo
+|   |   |   |   |-- memory_tests
+|   |   |   |   |-- mpu_tests
+|   |   |   |   |-- mtb_tests
+|   |   |   |   |-- romtable_tests
+|   |   |   |   |-- rtx_demo
+|   |   |   |   |-- self_reset_demo
+|   |   |   |   |-- sleep_demo
+|   |   |   |   |-- timer_driver_tests
+|   |   |   |   |-- timer_tests
+|   |   |   |   |-- uart_driver_tests
+|   |   |   |   |-- uart_tests
+|   |   |   |   |-- user_tests
+|   |   |   |   |-- vtor_tests
+|   |   |   |-- tools
+|   |   |   |-- v2html_doc
+|   |   |   |-- verilog
+```
+
+simulation setup (of the form):
+```
+  export ARM_PRODUCT_PATH=/apps/arm/developmentstudio-2021.0/sw/mappings
+  export ARM_TOOL_VARIANT=gold
+  export PATH=$PATH:/apps/arm/developmentstudio-2021.0/sw/ARMCompiler5.06u7/bin/
+```
+
+
+