message: Update README.md
  added static comipile example
diff: @@ -216,6 +216,16 @@ By using Swoole, you can build enhanced web applications with more control, real
  ./configure
  make && make install
  ```
  +3. Example for static compile:
  + ```
  + git clone -b PHP-7.2 --depth 1 https://github.com/php/php-src.git
  + cd php-src/
  + git clone -b master --depth 1 https://github.com/swoole/swoole-src.git ext/swoole
  + ./buildconf --force
  + ./configure --prefix=/usr/local/php7 --disable-all --enable-cli --disable-cgi --disable-fpm --disable-phpdbg --enable-bcmath --enable-hash --enable-json --enable-mbstring --enable-mbregex --enable-mbregex-backtrack --enable-sockets --enable-pdo --with-sodium --with-password-argon2 --with-sqlite3 --with-pdo-sqlite --with-pcre-regex --with-zlib --with-openssl-dir --enable-swoole-static --enable-openssl --with-swoole
  + time make -j `cat /proc/cpuinfo | grep processor | wc -l`
  + sudo make install
  + ```
  ## Introduction
  