Update README.md

Author: jkapuscik2

README.md

@@ -19,16 +19,16 @@ This project is set of simple examples of usage of different design patterns in
 - [visitor](https://medium.com/@j.kapuscik2/what-is-visitor-design-pattern-8451fb75876)
 - [command](https://medium.com/@j.kapuscik2/what-is-cqrs-command-design-pattern-5d400fd9f93a)
 
-Following patterns have so far been described:
+### Following patterns have so far been described:
 
-Creational:
+#### Creational:
 1. [Factory Method](/creational/factory_method)
 2. [Abstract Factory](/creational/abstract_factory)
 3. [Singleton](/creational/singleton)
 4. [Builder](/creational/builder)
 5. [Prototype](/creational/prototype)
 
-Behavioral:
+#### Behavioral:
 1. [Iterator](/behavioral/iterator)
 2. [Observer](/behavioral/observer)
 3. [State](/behavioral/state)
@@ -38,7 +38,7 @@ Behavioral:
 7. [Visitor](/behavioral/visitor)
 8. [Command](/behavioral/command)
 
-Structural:
+#### Structural:
 1. [Adapter](/structural/adapter)
 2. [Decorator](/structural/decorator)
 3. [Proxy](/structural/proxy)