Merging Getting Started section from manifest repo

This file should be a single entry point for meta-ohos documentation,
therefore Getting started section of manifest README was moved here.

Signed-off-by: Robert Drab <robert.drab@huawei.com>

README.md

-meta-ohos documentation
-=======================
+meta-ohos
+=========
 
-meta-ohos architecture is documented using [c4 model](https://c4model.com/).
+**meta-ohos** is a set of bitbake layers for building OpenHarmony images 
+using the bitbake infrastructure.
 
-## meta-ohos context diagram
-![meta-ohos system context diagram](./diagrams/meta-ohos_system_context_diagram.svg)
+[[_TOC_]]
+
+# Getting started
+
+## Prerequisites
+
+To start working with **meta-ohos** first install git repo:
+
+    $ sudo add-apt-repository ppa:zyga/oh-tools
+    $ sudo apt-get update
+    $ sudo apt-get install git-repo
+
+## Building OpenHarmony image
+
+Once git repo has been installed we can use it to clone the necessary repositories:
+
+    $ mkdir ohos; cd ohos
+    $ repo init -u https://git.ostc-eu.org/incubate/meta-ohos/manifest.git
+    $ repo sync
+    $ cd poky
+    poky$ . oe-init-build-env
+
+Working directory will automatically change to ./poky/build. Add layers for
+other kernels. Layers for poky were added automatically by sourcing
+`oe-init-build-env`.
+
+    build$ bitbake-layers add-layer ../meta-openembedded/meta-oe
+    build$ bitbake-layers add-layer ../meta-openembedded/meta-python
+    build$ bitbake-layers add-layer ../meta-zephyr
+    build$ bitbake-layers add-layer ../meta-freertos
+
+Build distro of your choice:
+
+For Poky-tiny you can choose any of the following machines:
+qemux86, qemux86-64, qemuarm, qemuarmv5
+
+    build$ DISTRO=poky-tiny MACHINE=qemux86 bitbake core-image-minimal
+
+
+For Zephyr you can choose any of the following machines:
+acrn, arduino-101-ble, arduino-101, arduino-101-sss, qemu-cortex-m3, qemu-nios2, qemu-x86
+
+    build$ DISTRO=zephyr MACHINE=qemu-x86 bitbake zephyr-philosophers
+
+For FreeRTOS you can choose any of the following machines: qemuarmv5.
+
+    build$ DISTRO=freertos MACHINE=qemuarmv5 bitbake freertos-demo
 
-## Architecture Decision Records
-All decisions for architecturally significant requirements are documented
-using [adr-tools](https://github.com/npryce/adr-tools) and stored in [adr](./adr) subdirectory.
+For Zephyr, `zephyr-philosophers` is the one of sample applications available
+in meta-zephyr layer by Yocto project. It's easy to build other samples using
+recipes available in `meta-zephyr/recipes-kernel/zephyr-kernel/` directory.
 
-Decisions are to be discussed within MR of a given decision md file.
+## Running OpenHarmony image
+
+When the build is finished, you can run the image by issuing:
+
+    # For poky
+    build$ runqemu qemux86 ramfs qemuparams="-nographic"
+    # For Zephyr
+    build$ DEPLOY_DIR_IMAGE=tmp-newlib/deploy/images/qemu-x86 runqemu qemu-x86
+    # For FreeRTOS
+    build$ runqemu qemuarmv5
+
+After successful bootup, you should see following:
+
+    # For Zephyr
+    Booting from ROM..*** Booting Zephyr OS build zephyr-v2.4.0  ***
+    Philosopher 0 [P: 3]  THINKING [  300 ms ]
+    Philosopher 1 [P: 2]   EATING  [  575 ms ]
+    Philosopher 2 [P: 1]        STARVING
+    Philosopher 3 [P: 0]   EATING  [  525 ms ]
+    Philosopher 4 [C: -1]  THINKING [  475 ms ]
+
+    # For poky
+    qemux86 login:
+    # Default login is _root_ without a password.
+    # After login you should see prompt:
+    root@qemux86:~#
+
+    # For FreeRTOS
+    ###### - FreeRTOS sample application -######
+    
+    A text may be entered using a keyboard.
+    It will be displayed when 'Enter' is pressed.
+    
+    Periodic task 10 secs
+    Waiting For Notification - Blocked...
+    Task1
+    Task1
+    You entered: "HelloFreeRTOS"
+    Unblocked
+    Notification Received
+    Waiting For Notification - Blocked...
+
+To exit qemu, you can either shut down the system:
+
+    root@qemux86:~# poweroff -f
+
+or close qemu using key combination:
+
+    Ctrl-a followed by 'x'
+
+
+# meta-ohos architecture
+
+All decisions for architecturally significant requirements are documented using 
+[adr-tools](https://github.com/npryce/adr-tools) and stored in [adr](./adr) subdirectory.
+Decisions are discussed within MR of a given decision md file.
+
+**meta-ohos** architecture is documented using [c4 model](https://c4model.com/).
+
+## meta-ohos overview
+
+![meta-ohos system context diagram](./diagrams/meta-ohos_system_context_diagram.svg)