Merge pull request #1521 from hmfaysal/patch-1

Update README.md

Author: Jeckerson

README.md

@@ -92,6 +92,7 @@ where a phalcon project resides.
 
 ```bash
 cd phalcon-devtools
+composer install
 ln -s $(pwd)/phalcon /usr/bin/phalcon
 chmod ugo+x /usr/bin/phalcon
 ```