Add build instructions to README

Signed-off-by: Dmitrii Zolotarev <dvzolotarev@gmail.com>

README.md

@@ -4,3 +4,22 @@ Kelvin Blockchain node
 [![Build Status](https://travis-ci.com/cellframe/kelvin-node.svg?branch=master)](https://travis-ci.com/cellframe/kelvin-node)
 
 [Kelvin node manual](https://github.com/cellframe/kelvin-node/wiki/Kelvin-Node)
+
+## Build
+
+The project uses CMake. To generate a Makefile run in the project root directory `git submodule init && git submodule update --remote && cmake .`.
+Or if don't clone the project yet, run `git clone --recursive <repo>` to clone it with all submodules. Then build the project as a regular CMake project.
+
+### Prerequsites
+
+To successfully complete of the build, you must have folgende prerequisites installed (packages are named as in Debian GNU/Linux 10 "buster", please found the corresponding packages for your distribution):
+
+* libjson-c-dev
+
+* libmemcached-dev (for libdap-server-core submodule)
+
+* libev-dev (for libdap-server-core submodule)
+
+* libmagic-dev (for libdap-server submodule)
+
+* libcurl4-openssl-dev | libcurl4-nss-dev | libcurl4-gnutls-dev (for libdap-server submodule)