+ chapter 3 - updated
+ chapter 4.1 - basic theory of testing
+ chapter 4.2 - spring test configuration options
+ chapter 2.5 - definition of more solutions
+ chapter 4.3.2 - annotation @ActiveProfiles
+ chapter 4.3.3 - profile testing annotations
+ chapter 4 - completed
+ general update (cleaning)
+ chapter 5.8 - Admin Interface
+ chapter 5 - links (actuator & admin) to GitHub added
+ chapter 5 - completed